Santo Tomás a town in Ensenada Municipality, Baja California, on the Pacific Coast of Mexico. Santo Tomás is a primarily a wine-growing region, though it is increasingly a tourist destination. It was originally the site of the Misión Santo Tomás de Aquino. After the mission was abandoned, it was taken as a post for the Mexican frontier garrison and for a time as the capital of the territory of Baja California. The town grew up east of the Mission site.