Tip: if you are bringing a 3-year-old, don't walk down through the entrance. It's a 750-foot drop and they will start complaining at about 200 feet. It's steep and the trail is wet in places and has steep dropoffs at just the spots where they will want to climb on the railings. The best stuff is in the "big room" anyway, which you can reach by elevator, and then it's still an hour-and-a-half walk around the inside perimeter of the cavern, and that's enough for your toddler.

The best parts of the cave, we were told, are on the guided tour, but you can't go with anyone under 4, because the guides turn the lights out at different spots so that folks can experience total darkness, and the ranger said that this tends to create panic in three-year-olds. I knew right away that Katie would be the panicing type, so we didn't lie about her age. Mark was going to go on the tour without us, but changed his mind and decided to walk around the big room with me and Katie. You'd have to ask him yourself, but I wonder if he regrets his decision: he got to experience me asking katie 67 times to stop singing (the rangers asked for silence, as the echo is great and folks try to experience the solitude of the cave. Although Katie's rendition of "ABC" is nice, it might not be the mantra they had in mind).

All in all, there are lots and lots of stalagtites and -mites, ponds, columns, and other pretty things to see, and the hugeness of it (Katie called it "hu-NOR-mous") is awe inspiring, even to the tune of "ABC."

Here are some pictures:

Here's the opening you walk down into

with lots of switchbacks...get used to em

Here's the way the bats see that opening, from inside. We didn't get to see the bats, because they're in Mexico for the winter, but in the summer they put on a show for folks at dusk when they swarm out by the thousands.

a tight spot in an otherwise cavernous cave

lots of stuff just didn't photograph at all in the dim light, especially the big big rooms. instead we got shots of close-up stuff like this