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 oversaw the construction of variable-toll express lanes and numerous redevelopments through the stretch of highway extending from Kirkman Road (SR 435; exit 75) in Orlando to SR 434 (exit 94) in Longwood. The project broke ground in 2015, and the express lanes opened to traffic on February 26, 2022. Previously, the median of I-4 between Tampa and Orlando was the planned route of a now-canceled 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.
