Its the original and Natural Bridge Caverns most popular tour, the Discovery Tour introduces you to an underground world of natural beauty and amazement. Travel through a half-mile of the largest and most spectacular show cavern in Texas. Youll walk 180 feet below the ground, while listening to our knowledgeable tour guide. See awe-inspiring, ancient formations centuries in the making and still growing today, such as amazing stalagmites, stalactites, flowstones, chandeliers and soda straws. Take pictures along the way because this is one walk through time that you will never want to forget. Departs every 40 minutes, or sooner throughout the day. Tour duration: 75 minutes. Cavern temperature is 70 degrees with a relative humidity of 99. Please wear comfortable walking shoes which provide good traction on steep, wet surfaces. Open daily but closed on Thanksgiving day, Christmas day, and New Years day. Other tours available; Hidden Passages and Lantern tours. Buy tickets online and save. $19; $11 child