San Juan de Ulúa, now known as Castle of San Juan de Ulúa, is a large complex of fortresses, prisons and one former palace on an island of the same name in the Gulf of Mexico overlooking the seaport of Veracruz, Mexico. Juan de Grijalva's 1518 expedition named the island. On March 30, 1519, Hernan Cortés met with Tendile and Pitalpitoque, emissaries from Moctezuma II's Aztec Empire.