On this day in Texas history, in 1968, HemisFair, the first officially designated international exposition in the southwestern United States, opened in San Antonio. It celebrated the cultural heritage shared by San Antonio and the nations of Latin America. It ran from April to October and attracted 6.3 million visitors. More than thirty nations participated with pavilions or exhibits. It also changed the face of the city. The outstanding structures at the fair that remained after the event included the Institute of Texan Cultures, the Convention Center and Arena, and the 622-foot Tower of the Americas.