In 1650, an expedition from Santa Fe led by Capts. Hernan Martin and Diego del Castillo explored the Concho River, 32 miles north of here, gathering information on Jumano Indians and searching for pearls. They traveled about 600 miles to Jumano territory, where they stayed for 6 months. Their further travels took them to the edge of the Texas nation, where they obtained the first definite information about the tribe that gave Texas its name. The discoveries of pearls and the Texas nation sparked later important Spanish expeditions to East Texas.