I-75 begins its national northward journey near Miami, running along the western parts of the Miami metropolitan area before traveling westward across Alligator Alley (also known as Everglades Parkway[2]), resuming its northward direction in Naples, running along Florida's Gulf Coast, and passing the cities of Fort Myers, Punta Gorda, Venice, and Sarasota.

The freeway passes through the Tampa Bay area before turning inward toward Ocala, Gainesville, and Lake City before leaving the state and entering Georgia.

Planning to extend the Interstate south to Miami began in 1968 after massive growth in Southwest Florida, which resulted in I-75 being realigned to travel on the eastern fringes of the Tampa Bay area, and the last portion of the highway was opened in 1993.

[3] As it curves around the border of Miami Lakes, I-75 serves some of the western fringes of South Florida as an eight-lane highway.

After an exit with SR 860, I-75 has an interchange with the Homestead Extension of Florida's Turnpike before crossing into Broward County.

There, it continues through the western suburbs of Pembroke Pines, Weston, Miramar, Davie, and Southwest Ranches.

[4] The highway's toll plazas accept both cash and transponders in the SunPass network and are located at either entrance to Alligator Alley.

There are two interchanges along the 75-mile (121 km) tolled portion of Alligator Alley in addition to three rest areas and a number of scenic outlook points as the highway crosses the Everglades.

[citation needed] Construction of the original route from the Georgia border to Tampa via Gainesville and Ocala lasted through most of the 1960s.

By mid-1964, I-75 opened from Lake City to the newly completed Florida's Turnpike (known then as the Sunshine State Parkway) in Wildwood.

Florida's state government first proposed to build a West Coast Turnpike in 1964 from the Tampa Bay area south to Naples.

[9] Plans for the West Coast Turnpike (which would have been tolled) were canceled in 1968, when it was announced that US Secretary of Transportation Alan S. Boyd had approved an extension of I-75 south to Naples and then east to Miami.

The federal government would pay for 90 percent of the extension using funds allocated by the Federal-Aid Highway Act of 1968, which was signed into law by President Lyndon B.

The bypass was initially planned to be designated Interstate 75E (I-75E), and was to split from I-75 near Wesley Chapel and rejoin it just north of Ellenton.

However, in 1972, it was determined that maintaining the main route of I-75 through Downtown Tampa would eventually require major improvements to the existing infrastructure to handle through traffic.

Additionally, Alligator Alley itself needed upgrading, as the then-narrow toll road was dangerous to both motorists and wildlife (most notably the Florida panther) alike, and the Dolphin Expressway, with its left exits and narrow lanes, was not being built to Interstate Highway standards, with the costs to upgrade it being too expensive.

By using this route, I-75 would run along the alley to the proposed Port Everglades Expressway, where it would turn south along a new freeway through the western suburbs of Weston and Pembroke Pines to Miami.

It was still planned to continue east to I-95, but, due to local opposition, I-75 was not built past its current terminus at SR 826 (Palmetto Expressway) in Hialeah.

[citation needed] The Alligator Alley segment of I-75 extends from a toll plaza just east of Naples to an interchange with I-595 and the Sawgrass Expressway (SR 869) in Sunrise just west of Fort Lauderdale.

However, as alligators often frequent the waterways beside the road, and occasionally the roadway itself, the nickname has developed a somewhat literal meaning.

The need to improve the road was one of the factors considered in the decision to reroute I-75 onto Alligator Alley, which was rebuilt as a four-lane Interstate Highway between 1986 and 1992.

The project completed another section of the South Florida managed lanes network for all motorists and improves mobility, relieves congestion, provides additional travel options, and accommodates future growth in the area.

[25] Another diverging diamond interchange with SR 56 (exit 275) was initially proposed in May 2018;[26] construction on the revamped intersection began in February 2019,[27] and it was completed in 2022.

In addition, there are separate facilities for each direction of the Interstate in Hamilton and Suwannee counties, southbound and northbound, respectively, and a welcome center south of the state line.

[31] Motorist-aid call boxes were installed starting in 1973, initially from the Georgia line to Lake City,[32] eventually being installed on both outside shoulders of the road every one mile (1.6 km) to allow drivers to indicate the need for gasoline, repair (tire or engine), or emergency services (police, ambulance, or fire).

The majority of the call boxes were removed in late 2013 because of the rising maintenance cost and the availability of newer technology.

In John D. MacDonald's novel, The Long Lavender Look, part of his series about fictional detective Travis McGee, the story takes place on Alligator Alley and in nearby towns accessible from it.