Wonder Cave in San Marcos may not be the most beautiful of the seven caverns in Texas open to the public, but it is unique. This is the only show cave created by an earthquake.
Descending 160 feet below the surface, the narrow walkway goes through a crack in the earth formed 15 million years ago by the Balcones Fault. Visitors can stand on the dividing line with one foot in the Hill Country and the other on the Coastal Plains.
The Balcones Fault line runs approximately 300 miles from Del Rio to Waco, roughly following I-35. When the continental plates collided, they pushed up the hills to the west and dropped the plains to the east. Scientists believe it is now one of the lowest-risk areas for earthquakes in the United States.
Wonder Cave was discovered in 1896 by a farmer drilling for water. The first exploration of the cave began on a cold day when the family noticed steam coming out of the ground behind their house. Early owners used the upper rooms as a gambling den and distillery. It became Texas’ first show cave in 1903 when the owners began charging a nickel for visitors to take unguided tours into its depths.
The walls of the cave are sharp and jagged rather than smooth like in other caves that were formed by centuries of water shaping the soft limestone. Referred to as a “dry-formed” cave, there are only a couple of formations created by dripping water and they are no longer growing. There are no spectacular stalactite and stalagmite formations.
What makes this cave interesting is seeing the layers of the earth’s crust. The walls are ribbons of colors and textures of the different kinds of rocks. At the lowest portion of the cave is the wishing well, where visitors can peer into the clear waters of the Edwards Aquifer. The ceiling of the last room of the tour is covered in fossilized tubes made in the ancient sea bed by tiny insects. The guides on the 45-minute underground tour are informative and entertaining as they share their stories about history and geology.
At the end of the tour, an elevator takes tour groups to the surface and up the 190-foot tower for a dramatic view of the Balcones Fault as it snakes along the landscape. Back on solid ground, tour groups are led through an anti-gravity house where water runs uphill. The tour ends with a short tram ride through a waterfall to an animal park to feed the tame deer and turkeys.
Wonder World is about a mile south of downtown San Marcos and a couple of miles west of I-35 at the Wonder World Drive exit. For more information, call 512/392-3760 or go to www.wonderworldpark.com.
1,001st in a series. Collect them all. Day Trips, Vol. 2, a book of “Day Trips” 101-200, is available for $8.95, plus $3.05 for shipping, handling, and tax. Mail to: Day Trips, PO Box 33284, South Austin, TX 78704.
This article appears in September 17 • 2010.
