Many people arrive expecting to find formations of crystal rock. But don’t be surprised: the name for these caves comes from the incredibly clear turquoise water in the pools within the caves, so clear in fact, that you can easily see the bottom through 55 feet of water.

There are, of course, plenty of formations for you to see. Guides will escort you along the pontoon bridges that crosses the pools (primarily to make sure you don’t touch the formations, which would interrupt their growth) and point out the incredible formation that resembles the Manhattan skyline. He or she is also likely to remind you of the difference between stalactites and stalagmites: stalactites grow down from the cave’s ceiling, while stalagmites grow up from the cave floor. Both grow slowly (1 cubic inch every 100 years) and depend on the remorseless dripping of water on stone. When stalactites and stalagmites meet and grow together, they are known simply as columns.

The Crystal Caves history goes back to 1907, when two boys discovered the caves when playing cricket. They immediately took a lantern and a piece of rope to explore them. Since then, these stalagmite and stalactite formations have been open to the public. Ask your guide to point out the original entrance (you can see a bit of skylight through it) — and be amazed at how brave (and agile!) the boys must have been to climb down to find this subterranean wonderland.

Be warned that visiting the caves requires climbing lots of steps and may not be appropriate if you’re at all claustrophobic.