Spelunking... in San Antonio?

On the second full day of our San Antonio getaway, our destination was Natural Bridge Caverns. Getting there took us in a different direction along San Antonio's loop road, by what we dubbed a "sci-fi city" along the highway.

As bizarre a sight as that might seem, our destination would strike many people as even more so -- the sort of place I'd have never imagined you could find in Texas. For decades, farm owners outside San Antonio had long known about the sinkhole on their land, marked by a "natural bridge" of remaining land.

In 1960, a group of students approached them to explore inside, and they discovered a series of limestone caverns curling around for more than a mile, to nearly 200 feet below ground. In a few years, the land owners had left farming behind to develop the caverns as a tourist attraction -- not unlike the Hana Lava Tube on Maui, but on a much larger (and admittedly, more commercialized) scale.

There's all sorts of features in the caverns, from columns and stalagmites to stalactites and soda straws to ribbons and curtains. There are huge, echoing chambers, and short, narrow tunnels. And the principle "Discovery Tour" is a go-at-your-own-pace trip, so you have plenty of time to take it all in.

We also took a second tour through the newer "Hidden Passages" section, which feels rather more "untamed." Instead of well-textured ramps, these passages were marked by hundreds of steep steps. The cave was even working slowly against intrusion, with a new calcite feature forming around a handrail at one point. This tour also included a few minutes in complete darkness deep inside the cave -- not much of a heart-fluttery moment with dozens of smartphone flashlights a pocket away, but nevertheless a chance to be impressed by the people who first explored these caverns with headlamps revealing only a few feet in front of them.

(In fact, for adventurous people looking for that kind of experience, Natural Bridge Caverns has you covered too. Each morning, they offer an "Adventure Tour" where you can actually be lowered into a cavern through its discovery well shaft, and then proceed to crawl through undeveloped passages. Too much for my claustrophobia to take, thank you very much, but it's there.)

Though unexpected, the Natural Bridge Caverns were an enjoyable stop on the trip. Who knows what may find you near San Antonio, but they're worth checking out.