thumb|The southern terminus of I-37 in Corpus Christi Construction in San Antonio also began in the 1960s and was completed in 1972. The first sections were completed in 1967 to include the portion just south of I-410 at the US 181 interchange. The section from Steves Avenue north to Florida Street to include the I-10 interchange was also complete in 1967. In 1968, the section south of I-410 was extended south to Loop 1604. In 1969, the two sections were connected with the completion of overpasses at Goliad Road, Pecan Valley Drive, Fair Avenue, and Hackberry Street as well as the completion of the interchanges at I-410 and Loop 13. The last sections left were on the eastside of downtown. The downtown overpasses at Durango Boulevard, Commerce Street, and the overpass stretching from Houston Street to Jones Avenue were all completed in 1972. The last portion completed in San Antonio was the stack interchange at I-35 (also known as the San Antonio "Downtown Mixer"), near the Pearl Brewery. With the completion of the interchange in 1972, the city had a complete freeway loop in conjunction with I-10 and I-35 around the central business district of the city. At the time construction began in July 1969, the I-35 interchange was the largest highway construction project in state history at $11 million (equivalent to $ in ).
thumb|The southern terminus of I-37 in Corpus Christi Construction in San Antonio also began in the 1960s and was completed in 1972 The first sections were completed in 1967 to include the portion just south of I-410 at the US 181 interchange The section from Steves Avenue north to Florida Street to include the I-10 interchange was also complete in 1967 In 1968 the section south of I-410 was extended south to Loop 1604 In 1969 the two sections were connected with the completion of overpasses at Goliad Road Pecan Valley Drive Fair Avenue and Hackberry Street as well as the completion of the interchanges at I-410 and Loop 13 The last sections left were on the eastside of downtown The downtown overpasses at Durango Boulevard Commerce Street and the overpass stretching from Houston Street to Jones Avenue were all completed in 1972 The last portion completed in San Antonio was the stack interchange at I-35 (also known as the San Antonio "Downtown Mixer") near the Pearl Brewery With the completion of the interchange in 1972 the city had a complete freeway loop in conjunction with I-10 and I-35 around the central business district of the city At the time construction began in July 1969 the I-35 interchange was the largest highway construction project in state history at $11 million (equivalent to $ in )