Interstate 37 (abbreviated 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 with construction beginning in the 1960s and completed in the 1980s. It begins in Corpus Christi at U.S. Route 181 (US 181) and State Highway 35 (SH 35), and heads north to San Antonio, where it ends at Interstate 35 (I-35). The freeway continues as US 281 beyond I-35 to northern San Antonio as a major freeway. 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.