Miami-Dade County, Florida
Images, from top down, left to right: Downtown Miami skyline; Lifeguard station on South Beach; Miami Design District's Palm Court; Wynwood Walls in Wynwood Art District; Ocean Drive in Miami Beach; Venetian Pool; Biscayne National Park; American Airlines Arena; Anhinga Trail boardwalk in Everglades National Park
"Dade County", "Dade", "Metro-Dade", "Greater Miami"
Delivering Excellence Every Day
|Coordinates: Coordinates: |
|Founded||January 18, 1836|
|Named for||Francis L. Dade|
|o Type||Two-tier federation|
|o Body||Miami-Dade Board of County Commissioners|
|o Miami-Dade Board of County Commissioners|
|o Mayor of Miami-Dade County||Daniella Levine Cava (D)|
|o Total||2,431.178 sq mi (6,296.72 km2)|
|o Land||1,898.753 sq mi (4,917.75 km2)|
|o Water||532.425 sq mi (1,378.97 km2) 21.9%|
|Highest elevation||34-40 ft (22 m)|
|Lowest elevation||0 ft (0 m)|
| o Estimate |
|o Density||1,000/sq mi (400/km2)|
|Time zone||UTC-5 (Eastern Time Zone)|
|o Summer (DST)||UTC-4 (Eastern Daylight Time)|
33002, 33010-33018, 33030-33035, 33039, 33054, 33056, 33090, 33092, 33101-33102, 33106, 33109, 33111-33112, 33114, 33116, 33119, 33122, 33124-33147, 33149-33158, 33160-33170, 33172-33199, 33206, 33222, 33231, 33233-33234, 33238-33239, 33242-33243, 33245, 33247, 33255-33257, 33261, 33265-33266, 33269, 33280, 33283, 33296, 33299
|GNIS feature ID||295755|
|Primary Airport||Miami International Airport (MIA)|
|Commuter Rail||Amtrak, Brightline, Tri-Rail|
Miami-Dade County is located in the southeastern part of the U.S. state of Florida. According to a 2019 census report, the county had a population of 2,716,940, making it the most populous county in Florida and the seventh-most populous county in the United States. It is also Florida's third largest county in terms of land area, with 1,946 square miles (5,040 km2). The county seat is Miami, the principal city in South Florida.
The county is home to 34 incorporated cities and many unincorporated areas. The northern, central and eastern portions of the county are heavily urbanized with many high-rise buildings along the coastline, including South Florida's central business district, Downtown Miami. Southern Miami-Dade County includes the Redland and Homestead areas, which make up the agricultural economy of the region. Agricultural Redland makes up roughly one third of Miami-Dade County's inhabited land area, and is sparsely populated, a stark contrast to the densely populated, urban northern portion of the county.
The county also includes portions of two national parks. To the west it extends into the Everglades National Park and is populated only by a Miccosukee tribal village. East of the mainland, in Biscayne Bay, is Biscayne National Park and the Biscayne Bay Aquatic Preserves.
The earliest evidence of Native American settlement in the Miami region came from about 12,000 years ago. The first inhabitants settled on the banks of the Miami River, with the main villages on the northern banks.
The inhabitants at the time of first European contact were the Tequesta people, who controlled much of southeastern Florida, including what is now Miami-Dade County, Broward County, and the southern part of Palm Beach County. The Tequesta Indians fished, hunted, and gathered the fruit and roots of plants for food, but did not practice agriculture. They buried the small bones of the deceased with the rest of the body, and put the larger bones in a box for the village people to see. The Tequesta are credited with making the Miami Circle.
Juan Ponce de León was the first European to visit the area in 1513 by sailing into Biscayne Bay. His journal records he reached Chequescha, a variant of Tequesta, which was Miami's first recorded name. It is unknown whether he came ashore or made contact with the natives. Pedro Menéndez de Avilés and his men made the first recorded landing when they visited the Tequesta settlement in 1566 while looking for Avilés' missing son, shipwrecked a year earlier. Spanish soldiers led by Father Francisco Villarreal built a Jesuit mission at the mouth of the Miami River a year later but it was short-lived. After the Spaniards left, the Tequesta Indians were left to fend themselves from European-introduced diseases like smallpox. By 1711, the Tequesta sent a couple of local chiefs to Havana, Cuba, to ask if they could migrate there. The Cubans sent two ships to help them, but Spanish illnesses struck and most of the Tequesta died.
The first permanent European settlers arrived in the early 19th century. People came from the Bahamas to South Florida and the Keys to hunt for treasure from the ships that ran aground on the treacherous Great Florida Reef. Some accepted Spanish land offers along the Miami River. At about the same time, the Seminole Indians arrived, along with a group of runaway slaves. The area was affected by the Second Seminole War, during which Major William S. Harney led several raids against the Indians. Most non-Indian residents were soldiers stationed at Fort Dallas. It was the most devastating Indian war in American history, causing almost a total loss of population in Miami.
After the Second Seminole War ended in 1842, William English re-established a plantation started by his uncle on the Miami River. He charted the "Village of Miami" on the south bank of the Miami River and sold several plots of land. In 1844, Miami became the county seat, and six years later a census reported there were ninety-six residents in the area. The Third Seminole War was not as destructive as the second, but it slowed the settlement of southeast Florida. At the end of the war, a few of the soldiers stayed.
Dade County was created on January 18, 1836, under the Territorial Act of the United States. The county was named after Major Francis L. Dade, a soldier killed in 1835 in the Second Seminole War, at what has since been named the Dade Battlefield. At the time of its creation, Dade County included the land that now contains Palm Beach and Broward counties, together with the Florida Keys from Bahia Honda Key north and the land of present-day Miami-Dade County. The county seat was originally at Indian Key in the Florida Keys; then in 1844, the County seat was moved to Miami. The Florida Keys from Key Largo to Bahia Honda were returned to Monroe County in 1866. In 1888 the county seat was moved to Juno, near present-day Juno Beach, Florida, returning to Miami in 1899. In 1909, Palm Beach County was formed from the northern portion of what was Dade County, and then in 1915, Palm Beach County and Dade County contributed nearly equal portions of land to create what is now Broward County. There have been no significant boundary changes to the county since 1915.
The third-costliest natural disaster to occur in the United States was Hurricane Andrew, which hit Miami in the early morning of Monday, August 24, 1992. It struck the southern part of the county from due east, south of Miami and very near Homestead, Kendall, and Cutler Ridge (now the Town of Cutler Bay). Damages numbered over US$25 billion in the county alone, and recovery has taken years in these areas where the destruction was greatest. This was the costliest natural disaster in US history until Hurricane Katrina struck the Gulf region in 2005.
On November 13, 1997, voters changed the name of the county from Dade to Miami-Dade to acknowledge the international name recognition of Miami. Voters were acting pursuant to home rule powers granted to Dade County, including the ability to change the name of the county without the consent of the Florida Legislature. The change in name also addressed a source of public dissatisfaction with the name "Dade" which was chosen to honor Francis L. Dade, who had been killed in the Dade Massacre in the 1830s. The massacre did not occur in South Florida, but in the west central part of the state, in present-day Sumter County, near Bushnell. There is also a Dade City, which is closer to the site of the massacre.
|Climate chart (explanation)|
According to the U.S. Census Bureau, the county has an area of 2,431 square miles (6,300 km2), of which 1,898 square miles (4,920 km2) is land and 533 square miles (1,380 km2) (21.9%) is water. It is the third-largest county in Florida by land area and second-largest by total area. Most of the water is in the Biscayne Bay, with another significant portion in the adjacent Atlantic Ocean.
Miami-Dade County is only about 6 feet (1.8 m) above sea level. It is rather new geologically and is at the eastern edge of the Florida Platform, a carbonate plateau created millions of years ago. Eastern Dade is composed of Oolite limestone while western Dade is composed mostly of Bryozoa. Miami-Dade is among the last areas of Florida to be created and populated with fauna and flora, mostly in the Pleistocene.
The bay is divided from the Atlantic Ocean by the many barrier isles along the coast, one of which is where well-known Miami Beach is located, home to South Beach and the Art Deco district. The Florida Keys, which are also barrier islands are only accessible through Miami-Dade County, but which are otherwise part of neighboring Monroe County. Miami is sixty-five miles from West Palm Beach, and thirty miles from Fort Lauderdale.
In 2010, the largest ancestry groups were:
In 2010, Cubans made up the largest population of immigrants (with more than half of the population) with Colombians coming in second, Haitians in third, followed by Nicaraguans in fourth place, then Dominicans, Venezuelans, Peruvians, Jamaicans, Mexicans, and Argentinians among the highest group of immigrants.
Miami-Dade has small communities of Brazilians, Portuguese, Spaniards, Ukrainians and Poles along with Canadians (including Francophone from the province of Quebec), French, Germans, other Europeans, British expatriates and Israelis
There were 867,352 households, out of which 30.6% had children under the age of 18 living with them, 43.8% were married couples living together, 18.8% had a female householder with no husband present, and 30.5% were non-families. 23.6% of all households were made up of individuals, and 8.4% (2.5% male and 5.9% female) had someone living alone who was 65 years of age or older. The average household size was 2.83 and the average family size was 3.33.
The age distribution is 21.9% under the age of 18, 9.9% from 18 to 24, 28.6% from 25 to 44, 25.6% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 38.2 years. For every 100 females, there were 93.8 males. For every 100 females age 18 and over, there were 91.0 males.
The median income for a household in the county was $43,605, and the median income for a family was $50,065. Males had a median income of $35,096 versus $29,980 for females. The per capita income for the county was $22,957. About 13.8% of families and 17.2% of the population were below the poverty line, including 22.0% of those under age 18 and 22.1% of those aged 65 or over.
In 2010, 51.1% of the county's population was foreign born, with 48.7% being naturalized American citizens. Of foreign-born residents, 93.0% were born in Latin America, 3.2% were born in Europe, 2.7% born in Asia, 0.5% born in Africa, 0.5% in North America, and 0.1% were born in Oceania.
As of the census of 2000, there were 2,253,362 people, 776,774 households, and 548,402 families in the county, with an average population density of 1,158 inhabitants per square mile (447/km2). There were 852,278 housing units with an average density of 438 per square mile (169/km2). The county's racial makeup was 69.7% White (49% White Hispanic, 20.7% Non-Hispanic White), 20.3% African American and Black (with a large part of Caribbean descent), 0.2% Native American, 1.4% Asian, <0.1% Pacific Islander, 4.60% from other races, and 3.8% from two or more races. 57.3% of the population were Hispanic or Latino of any race. In relation to ancestry (excluding the various Hispanic and Latino ancestries), 5% were Haitian, 5% American, 2% Italian, 2% Jamaican, 2% German, 2% Irish, and 2% English ancestry.
There were 776,774 households, out of which 33.8% had children under the age of 18 living with them, 47.7% were married couples living together, 17.2% had a female householder with no husband present, and 29.4% were non-families. 23.3% of all households were made up of individuals, and 8.6% had someone living alone who was 65 years of age or older. The average household size was 2.84 and the average family size was 3.35.
The age distribution is 24.8% under the age of 18, 9.1% from 18 to 24, 31.0% from 25 to 44, 21.7% from 45 to 64, and 13.3% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 93.5 males. For every 100 females age 18 and over, there were 90.2 males.
The county's median household income was $35,966, and the median family income was $40,260. Males had a median income of $30,120 versus $24,686 for females. The county's per capita income was $18,497. About 14.5% of families and 18.0% of the population were below the poverty line, including 22.9% of those under age 18 and 18.9% of those age 65 or over.
As of 2010, 28.1% of the population spoke only English at home, while 63.8% of the population spoke Spanish, 4.2% spoke French Creole (mainly Haitian Creole), 0.6% French, and 0.6% Portuguese. About 52% of the county residents were born outside the United States, while 71.9% of the population spoke a language other than English at home.
In 2010 statistics, the largest religious group in Miami-Dade County was the Archdiocese of Miami with 544,449 Catholics in 65 parishes, followed by 96,749 non-denominational adherents with 197 congregations, 80,123 SBC Baptists with 313 congregations, 47,921 NBC Baptists with 44 congregations, 27,901 Seventh-day Adventists in 62 congregations, 25,244 AoG Pentecostals with 45 congregations, an estimated 23,064 Muslims with 15 congregations, 14,628 LDS Mormons with 18 congregations, 12,569 TEC Episcopalians with 30 congregations, and 11,880 UMC Methodists with 32 congregations. Altogether, 39.8% of the population was claimed as members by religious congregations, although members of historically African-American denominations were underrepresented due to incomplete information. In 2014, Miami-Dade County had 731 religious organizations, the 14th most out of all US counties.
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Miami-Dade County has operated under a unique metropolitan system of government, a "two-tier federation", since 1957. This was made possible when Florida voters approved a constitutional amendment in 1956 that allowed the people of Dade County (as it was known) to enact a home rule charter. Prior to this year, home rule did not exist in Florida, and all counties were limited to the same set of powers by the Florida Constitution and state law.
Unlike a consolidated city-county, where the city and county governments merge into a single entity, these two entities are separate. Instead there are two "tiers", or levels, of government: city and county. There are 34 municipalities in the county, the City of Miami being the largest.
Cities are the "lower tier" of local government, providing police and fire protection, zoning and code enforcement, and other typical city services within their jurisdiction. These services are paid for by city taxes. The County is the "upper tier", and it provides services of a metropolitan nature, such as emergency management, airport and seaport operations, public housing and health care services, transportation, environmental services, solid waste disposal etc. These are funded by county taxes, which are assessed on all incorporated and unincorporated areas.
Of the county's 2.6 million total residents (as of 2013), approximately 52% live in unincorporated areas, the majority of which are heavily suburbanized. These residents are part of the Unincorporated Municipal Services Area (UMSA). For these residents, the County fills the role of both lower- and upper-tier government, the County Commission acting as their lower-tier municipal representative body. Residents within UMSA pay a UMSA tax, equivalent to a city tax, which is used to provide County residents with equivalent city services (police, fire, zoning, water and sewer, etc.). Residents of incorporated areas do not pay UMSA tax.
The Mayor of Miami-Dade County is elected countywide to serve a four-year term and is considered a "strong mayor". The mayor is not a member of the County Commission, appoints all 25 directors who oversee the operations of the County Departments and has veto power over the Commission. A mayoral appointment and veto can only be overridden by a two-thirds majority of the County Commission. The post is occupied by Daniella Levine Cava, the county's first female mayor.
The Board of County Commissioners is the legislative body, consisting of 13 members elected from single-member districts. Members are elected to serve four-year terms, and elections of members are staggered. The Board chooses a Chairperson, who presides over the Commission, as well as appoints the members of its legislative committees. The Board has a wide array of powers to enact legislation, create departments, and regulate businesses operating within the County. It also has the power to override the Mayor's veto with a two-thirds vote.
Florida's Constitution provides for six elected officials to oversee executive and administrative functions for each county (called "Constitutional Officers"): Sheriff, Property Appraiser, Supervisor of Elections, Tax Collector, Clerk of the Circuit Court and Comptroller. However, the Constitution allows voters in home-rule counties (including Miami-Dade) to abolish the offices and reorganize them as subordinate County departments; Miami-Dade voters chose this option for Sheriff, Supervisor of Elections, Controller and Tax Collector. The office of Clerk of the Circuit Court, and the judicial offices of State Attorney, and Public Defender, are still branches of State government and are, therefore, independently elected and not part of County government.
Miami-Dade is the only county in Florida that does not have an elected sheriff or a "Sheriff's Office". Instead, the county's law enforcement agency is known as the Miami-Dade Police Department, and its leader is known as the Metropolitan Sheriff and Director of the Miami-Dade Police Department. (Nonetheless, Miami-Dade Police badges bear the inscription, "Deputy Sheriff, Sheriff's Office, Dade County, Fla.".)
Miami-Dade County has voted for the Democratic Party candidate in most of the presidential elections in the past four decades, and has gone Democratic in every election since 1992. However, it did vote twice for Ronald Reagan (1980, 1984) and once for George H. W. Bush (1988). From 1904 to 1972 it supported the Democratic candidate in all but four elections. The Democrats had expanded their winning margin in each of the three elections from 2008 to 2016; in 2008 and 2012, Democrat Barack Obama won 59.69% of the vote. In 2016, Democrat Hillary Clinton won 63.22% of the vote. However, in 2020, Democrat Joe Biden only won 53.31% of the vote, winning the county by just over seven percent over Republican Donald Trump. This was attributed to a large swing of Cuban Americans and Venezuelan Americans to the Republican Party.
Miami-Dade County is represented in the United States House of Representatives by Republicans Maria Elvira Salazar, Carlos Gimenez and Mario Diaz-Balart of the 27th, 26th and 25th districts, and Democrats Frederica Wilson and Debbie Wasserman Schultz of the 24th and 23rd districts.
|Registered voters as of 11/2/2020|
|Total population||2,716,940 (as of 7/1/2019)|
|No party preference||485,338||30.81%|
Brightstar Corporation,Burger King, Intradeco Holdings,Latin Flavors,Norwegian Cruise Line, and Ryder have their headquarters in unincorporated areas in the county.Centurion Air Cargo, Florida West International Airways, IBC Airways, and World Atlantic Airlines have their headquarters on the grounds of Miami International Airport in an unincorporated area in the county.
Other companies with offices in an unincorporated area not in any CDP:
After Frank Borman became president of Eastern Airlines in 1975, he moved Eastern's headquarters from Rockefeller Center in Midtown Manhattan, New York City to an unincorporated area in Miami-Dade County Around 1991 the Miami-Dade County lost a few corporations, including Eastern Airlines, which folded in 1991.
According to Miami's Beacon Council, the top private employers in 2014 in Miami-Dade were:
|#||Employer||# of employees|
|1||University of Miami||12,818|
|2||Baptist Health South Florida||11,353|
|4||Carnival Cruise Lines||3,500|
|5||Miami Children's Hospital||3,500|
|6||Mount Sinai Medical Center||3,321|
|7||Florida Power and Light Co.||3,011|
|8||Royal Caribbean International||2,989|
|10||Bank of America||2,000|
According to Miami's Beacon Council, the top government employers in 2014 in the county were:
|#||Employer||# of employees|
|1||Miami-Dade County Public Schools||33,477|
|4||Florida State Government||17,100|
|5||Jackson Health System||9,800|
The Miami-Dade County Fire Rescue Department is the agency that provides fire protection and emergency medical services for Miami-Dade County, Florida. The department serves 29 municipalities and all unincorporated areas of Miami-Dade County from 60 fire stations. The Department also provides fire protection services for Miami International Airport, Miami Executive Airport and Opa-locka Airport.
The communities served are Aventura, Bal Harbour, Bay Harbor Islands, Biscayne Park, Cutler Bay, Doral, El Portal, Florida City, Golden Beach, Hialeah Gardens, Homestead, Indian Creek, Medley, Miami Gardens, Miami Lakes, Miami Shores, Miami Springs, North Bay Village, North Miami, North Miami Beach, Opa-locka, Palmetto Bay, Pinecrest, South Miami, Surfside, Sweetwater, Sunny Isles Beach, Virginia Gardens, and West Miami.
Miami-Dade Fire Rescue is also the home to Urban Search and Rescue Florida Task Force 1 as well as EMS operations consisting of 57 Advanced Life Support units staffed by 760 state-certified paramedics and 640 state-certified emergency medical technicians.
The Miami-Dade Police Department is a full-service metropolitan police department serving Miami-Dade County's unincorporated areas, although it has lenient mutual aid agreements with other municipalities, most often the City of Miami Police Department. With 4,700 employees, it is Florida's largest police department. The Department is often referred to by its former name, the Metro-Dade Police or simply Metro.
The Miami-Dade Police Department operates out of nine districts throughout the county and has two special bureaus. The director of the department is Juan Perez, who succeeded J.D. Patterson, Jr. The Department's headquarters are in Doral, Florida.
Miami-Dade Water and Sewer Department (MDWASD) is one of the largest public utilities in the United States, employing approximately 2,700 employees as of 2007. It provides service to over 2.4 million customers, operating with an annual budget of almost $400 million. Approximately 330 million gallons of water are drawn every day from the Biscayne Aquifer for consumer use. MDWASD has over 7,100 miles (11,400 km) of water lines, a service area of 396 square miles (1,026 km2) and 14 pump stations. MDWASD has over 3,600 miles (5,800 km) of sewage pipes, a service area of 341 square miles (883 km2) and 954 pump stations. Miami-Dade County is also in the jurisdiction of the South Dade Soil and Water Conservation District.
Miami-Dade County Corrections and Rehabilitation Department is the correction agency.
The Miami-Dade Aviation Department (MDAD) operates Miami International Airport, Miami Executive Airport, Opa-locka Executive Airport, Homestead General Aviation Airport, and Dade-Collier Training and Transition Airport.
The Miami-Dade Public Library System traces its origin to the late nineteenth century. The first library was a reading room established in Lemon City on April 7, 1894 by the Lemon City Library and Improvement Association. In 1942 neighborhood libraries were brought together in a single public library system, governed by a Board of Trustees and administered by a Head Librarian. A new central library building had been proposed for Bayfront Park in Downtown Miami as early as 1938, but the proposal was not realized till over a decade later. In December 1965 the City of Miami and Metropolitan Dade County agreed that the City of Miami would provide public library service to unincorporated Dade County and to those municipalities that did not provide their library service with four bookmobiles provided library service to the unincorporated area. On November 1, 1971, the City of Miami transferred its library system to Metropolitan Dade County which created a new Department of Libraries with a Director reporting directly to the County Manager.
On November 7, 1972, Dade County voters approved a referendum, also known as the "Decade of Progress" bonds, authorized approximately $553 million for public improvement projects in Dade County. Of that amount, approximately $34.7 million was authorized for public libraries, including construction, renovation, land acquisition, furnishings, and equipment. Between 1976 and 1990, this bond issue provided the funds to open 14 new libraries.  On August 24, 1992, Hurricane Andrew inflicted significant damage on the library system, destroying all branches south of Kendall Drive. Over the next years, no further expansion of the system was funded and no new libraries opened. It wasn't until the fall of 2001, when Mayor Alex Penelas and Board of County Commissioners voted to increase the library system's budget which provided funding for capital improvement initiatives--making way for the opening of 18 new libraries by the year 2011.
Today Miami-Dade Public Library System serves a population of 2,496,435, provides services for the Miami-Dade County except for the cities of Bal Harbour, Hialeah, Miami Shores, North Miami, North Miami Beach and Surfside. It has fifty branches, two bookmobiles and one technobus. The Miami-Dade County Board of County Commissioners governs the Miami-Dade Public Library System.
In Florida, each county is also a school district. Miami-Dade County Public Schools, is operated by an independently elected School Board. A professional Superintendent of Schools appointed by the School Board manages the district's day-to-day operations. As of 2014 , the Miami-Dade County Public School District is the fourth-largest public school district in the nation with almost 360,000 students.
Miami-Dade County is home to many private and public universities and colleges.
Miami-Dade County holds the majority of sports arenas, stadiums and complexes in South Florida. Some of these sports facilities are:
Former venues include:
Miami International Airport, in an unincorporated area in the county, is the Miami area's primary international airport. One of the busiest international airports in the world, it serves over 35 million passengers a year. Identifiable locally, as well as several worldwide authorities, as MIA or KMIA, the airport is a major hub and the single largest international gateway for American Airlines, the world's largest passenger air carrier. Miami International is the United States' third largest international port of entry for foreign air passengers (behind New York's John F. Kennedy International Airport and Los Angeles International Airport), and is the seventh largest such gateway in the world. The airport's extensive international route network includes non-stop flights to over seventy international cities in North and South America, Europe, Asia, and the Middle East.
Public transit in Miami-Dade County is operated by Miami-Dade Transit, and is the largest public transit in Florida. Miami-Dade Transit operates a heavy rail metro system Metrorail, an elevated people mover in Downtown Miami, Metromover and the bus system, Metrobus.
Miami-Dade County has 10 major expressways and 1 minor expressway in Downtown Miami.
This is a list of Miami-Dade county roads. Miami-Dade County has fewer county roads than any other county in Florida, despite its large population. None are signed.
|#||Road Name(s)||Direction and Termini||Notes|
|Ives Dairy Road||SR 817||US 1||former SR 854 (east of US 441)|
|Crandon Boulevard / Rickenbacker Causeway||extension of SR 913|
|Lindgren Road||extension of SR 825|
|Southwest 57th Avenue||extension of SR 959|
|Galloway Road||extension of SR 973|
|Coral Reef Drive||extension of SR 992|
|Northwest 67th Avenue
Northwest 68th Avenue
|N/S||SR 826||Palm Springs North||Broward County line||Palm Springs North|
A street grid stretches from downtown Miami throughout the county. This grid was adopted by the City of Miami following World War I after the United States Post Office threatened to cease mail deliveries in the city because the original system of named streets, with names often changing every few blocks and multiple streets in the city sharing the same name, was too confusing for the mail carriers. The new grid was later extended throughout the county as the population grew west, south, and north of city limits.
The grid is laid out with Miami Avenue as the meridian going north-south and Flagler Street the baseline going east-west. The grid is primarily numerical so that, for example, all street addresses north of Flagler and west of Miami Avenue have NW in their address (e.g. NW 27th Avenue). Because its point of origin is in downtown Miami which is close to the coast, the NW and SW quadrants are much larger than the SE and NE quadrants. Many roads, especially major ones, are also named, although, with a few notable exceptions, the number is in more common usage among locals.
Although this grid is easy to understand once one is oriented to it, it is not universal in the entire county. Hialeah uses its own grid system which is entirely different in its orientation. Coral Gables and Miami Lakes use named streets almost exclusively, and various smaller municipalities such as Florida City and Homestead use their own grid system along with the Miami-Dade grid system adding to the confusion. In the beach cities and parks of Miami Beach, Surfside, Bal Harbour, Sunny Isles, and Golden Beach, the streets are coordinated with the main grid; however, their avenues are named.
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