He also commissioned the Juan Pardo expedition, to travel from Santa Elena, at Port Royal Sound in present-day South Carolina, into the interior of the Southeast. Captain Pardo was to find and supply an alternate overland route to the Spanish silver mines in central Mexico, as the Spanish mistakenly thought the Appalachian Mountains were part of a range extending that far. In the next couple of years, Pardo and his men traveled into present-day South Carolina and Western North Carolina, stopping at the Mississippian chiefdom of Joara, where they built Fort San Juan and wintered over. In total, his expedition built six forts along this route, extending as far as one known as San Pedro at Chiaha in southeastern Tennessee. Pardo left the expedition for other business. In 1568 all the Spanish men but one in the garrisons were killed by Native Americans resisting their treatment, and the forts were destroyed. The Spanish did not attempt other colonization in this region.