San Antonio is a major city in south-central Texas with a rich colonial heritage. The Alamo, an 18th-century Spanish mission preserved as a museum, marks an infamous 1836 battle for Texan independence from Mexico. Following the San Antonio River, the miles-long River Walk is a landmark pedestrian promenade lined with cafes and shops. Hemis Fair Park’s 750-ft. Tower of the Americas overlooks the city. San Antonio is the second-most-populous city in Texas.