Interstate 37

Interstate 37 (I-37) is a 143.0-mile (230.1 km) intrastate Interstate Highway located within the U.S. state of Texas. The highway was first designated in 1959 as a route between Corpus Christi and San Antonio. Construction in the urban areas of Corpus Christi and San Antonio began in the 1960s and the segments of the Interstate Highway in rural areas were completed by the 1980s. Prior to I-37, the route between Corpus Christi and San Antonio was served by a combination of State Highway 9 (SH 9) from Corpus Christi to Three Rivers and U.S. 281 (US 281) from Three Rivers to San Antonio. As a result of the construction of I-37, SH 9 was removed from the State Highway System.

The highway's southern terminus is located in Corpus Christi at US 181 and SH 35, and heads north to San Antonio, where it ends at I-35. The freeway continues as US 281 beyond I-35 to northern San Antonio as a major freeway. In Corpus Christi, the highway provides access to the downtown area, the Port of Corpus Christi and the Corpus Christi International Airport. In San Antonio, it provides access to Downtown, Brooks City-Base, the Alamodome, the Tower of the Americas, the River Walk, the Alamo, and by extension via US 281, the San Antonio International Airport. The route provides an important connection between I-35 and the Texas Gulf Coast as well as one of the few limited-access hurricane evacuation routes away from the southern Texas coast.