Interstate 4

Interstate 4 (I-4) is an Interstate Highway located entirely within the U.S. state of Florida, maintained by the Florida Department of Transportation (FDOT). Spanning 132.298 miles (212.913 km) along a generally southwest–northeast axis, I-4 is entirely concurrent with State Road 400 (SR 400). In the west, they begin at an interchange with I-275 in Tampa. They intersect with several major expressways as they traverse Central Florida, including US 41 in Tampa; US 301 near Riverview; I-75 near Brandon; US 98 in Lakeland; US 192 in Celebration; Florida's Turnpike in Orlando; and US 17 and US 92 in multiple junctions. In the east, I-4 ends at an interchange with I-95 in Daytona Beach, while SR 400 continues for roughly another 4 miles (6.4 km) and ends at an intersection with US 1 on the city line of Daytona Beach and South Daytona.

Construction on I-4 began in 1958; the first segment opened in 1959, and the entire highway was completed in 1965. The "I-4 Ultimate" project, currently in progress, will oversee the construction of variable-toll express lanes and numerous redevelopments through the 21-mile (34 km) stretch of highway extending from Kirkman Road (exit 75) in Orlando to SR 434 (exit 94) in Longwood. The project broke ground in 2015, and is scheduled to be completed in 2021 (actual completion time will vary slightly due to the ongoing COVID-19 pandemic). Previously, the median of I-4 between Tampa and Orlando was the planned route of a now-cancelled high-speed rail line. From a political standpoint, the "I-4 corridor" is a strategic region given the large number of undecided voters in a large swing state.