Natural Bridge Caverns is a network of underground caves located in San Antonio, Texas. It is one of the largest commercial caverns in the state and offers guided tours for visitors to explore the stunning rock formations and underground passageways. The caverns were formed over thousands of years through the natural process of erosion and are a popular tourist attraction in the area. Visitors can also enjoy other activities such as gemstone mining, zip-lining, and a maze challenge at Natural Bridge Caverns.