About 12 miles west of San Antonio, an otherworldly experience transports visitors to a different dimension. The subterranean Natural Bridge Caverns (26495 Natural Bridge Caverns Rd., 210/651-6101, www.naturalbridgecaverns.com, Oct.–Feb. 9 a.m.–4 p.m. daily, summer hours vary, $17–$26 adults, $10–15 children 3–11) is a good way to escape the Texas heat in the summer (the caverns’ temperature is a steady 70 degrees, but the 99 percent humidity feels like Houston).

Visitors descend nearly 200 feet below ground via cement walkways to a surreal world of ancient natural formations with expressive names like soda straws, chandeliers, flowstones, and cave ribbon. Parents be advised: Wait until the kids are at least 4 or 5 years old since strollers are difficult to operate and toddlers might not have the patience or interest.

Two tours are available, the standard North Cavern Tour, a 75-minute half-mile trek past oooh-inducing stalagmites, stalactites, flowstones, and other formations, some with descriptive titles such as the King’s Throne and Sherwood’s Forest. The other option, the Jeremy Room Flashlight Tour, takes place in a 120-foot deep chamber filled with some of the more delicate formations—particularly the brittle yet mesmerizing soda straws.

Each person gets a flashlight to check out the nooks and crannies of this space at his or her leisure. For those who really want to get up close and personal with the cavern, sign up for one of the Adventure Tours ($70–100), a physically demanding excursion allowing visitors to climb, rappel, and explore the cavern; this tour lasts three or more hours. Caving gear is provided.