The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA, pronounced Ice-Tea) is a United States federal law that posed a major change to transportation planning and policy, as the first U.S. federal legislation on the subject in the post-Interstate Highway System era. Objective The act presented an overall intermodal approach to highway and transit funding with collaborative planning requirements, giving significant additional powers to metropolitan planning organizations (MPOs). The act was signed into law on December 18, 1991, by President George H. W. Bush and codified as and . The bill was preceded by the Surface Transportation and Uniform Relocation Assistance Act in 1987 and followed by the Transportation Equity Act for the 21st Century (TEA-21) in 1998, the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) in 2005, the Moving Ahead for Progress in the 21st Century Act (MAP-21) in 2012, the FIxing America's Surface Transportation Act (FAST) in 2015, and the Infrastructure Investment and Jobs Act in 2021. ISTEA also provided funds for the conversion of dormant railroad corridors into rail trails; the first rail trail to be funded was the Cedar Lake Regional Rail Trail, in Minneapolis, Minnesota. High priority corridors Section 1105 of the act also defines a number of High Priority Corridors, to be part of the National Highway System. After various amendments in subsequent transportation bills and other legislation, this is a list of the corridors: High-speed rail corridors The legislation also called for the designation of up to five high-speed rail corridors. The options were studied for several months, and announced in October 1992. The first four were announced by United States Secretary of Transportation Andrew Card, while the last was announced by Federal Railroad Administration head Gil Carmichael. October 15, 1992: The Midwest high-speed rail corridor with three links from Chicago, Illinois to Detroit, Michigan, St. Louis, Missouri, and Milwaukee, Wisconsin. October 16, 1992: The Florida high-speed rail corridor linking Miami with Orlando and Tampa. October 19, 1992: The California high-speed rail corridor linking San Diego and Los Angeles with the San Francisco Bay Area and Sacramento via the San Joaquin Valley. October 20, 1992: The Southeast high-speed rail corridor connecting Charlotte, North Carolina, Richmond, Virginia, and Washington, D.C. October 20, 1992: The Pacific Northwest high-speed rail corridor linking Eugene and Portland, Oregon with Seattle, Washington and Vancouver, British Columbia, Canada. However, there was not significant funding attached