Interstate 75 in Florida

Interstate 75 (I-75) is a part of the Interstate Highway System that runs from the Hialeah–Miami Lakes border, a few miles northwest of Miami, to Sault Ste. Marie in the Upper Peninsula of Michigan. 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), 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. I-75 runs for 471 miles (758 km) in Florida, making it the longest Interstate in the state and also the longest in any state east of the Mississippi River. The Interstate's speed limit is 70 mph (110 km/h) for its entire length in Florida.

The portion of I-75 from Tampa northward was a part of the original 1955 Interstate Highway plans, with I-75's southern terminus at I-4's current western terminus. 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.

For Florida Department of Transportation (FDOT) inventory purposes, it is designated as State Road 93 (SR 93) for most of its length in Florida (with exception to the Tampa Bay area, where SR 93 follows I-275, while SR 93A travels with I-75 in the latter's bypass of the area).

I-75 begins its northward journey at an interchange with SR 826 (Palmetto Expressway) and SR 924 (Gratigny Parkway) on the Hialeah–Miami Lakes border, near Miami.

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.

At the junction of SR 869 (Sawgrass Expressway) and I-595, I-75 (while maintaining its south–north status) enters a west–east trajectory as it crosses the Everglades by way of Alligator Alley, a toll road that runs from the Collier Boulevard (exit 101) toll plaza to the U.S. Highway 27 (US 27) toll plaza (exit 23). It was originally constructed as a two-lane highway before it was converted to a four-lane highway meeting Interstate Highway standards. At this point, I-75 loses a lane in each direction, heading west, losing another lane west of the US 27 interchange.

The Alligator Alley section of I-75 runs due east–west between exit 19 in Sunrise and exit 101 just east of Naples and is one of only two sections along the Interstate's entirety that is tolled (the other is the Mackinac Bridge in northern Michigan). Tolls are $3.75 for a two-axle vehicle as of July 1, 2023, and are collected in both directions. The highway's toll plazas accept both cash and transponders in the SunPass network and are located at either entrance to Alligator Alley. The toll facilities along Alligator Alley and toll revenue collected from them are overseen by Florida's Turnpike Enterprise (FTE). 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. I-75 enters Collier County along Alligator Alley just west of the Snake Road exit (exit 49) and passes through the Big Cypress National Preserve between the Collier County border and SR 29 (exit 80). Several small bridges along Alligator Alley allow wildlife to pass safely under the freeway, especially along the Florida Panther National Wildlife Refuge east of SR 29. Extensive fencing also prevents wildlife from interfering with traffic.

As it approaches Naples at County Road 951 (CR 951; exit 101), Alligator Alley ends. The Interstate is toll-free for the rest of its length in Florida and makes a sharp turn north, resuming its north–south trajectory, and as it parallels Florida's west coast, it becomes six lanes. As it continues north, I-75 passes near Bonita Springs, Fort Myers, Punta Gorda, Port Charlotte, Venice, Sarasota, and Bradenton before reaching the Tampa Bay area metropolis consisting of Tampa and St. Petersburg.