Where's Nemo?  Follow the trail and find out...
historic_entrance

Heading down to Tennesse to see mom, I stopped at Mammoth Cave National Park...
park_sign

We had a five-minute bus ride from the visitor center to the cave...
cave_bus

Here's Ranger Kevin and the entrance...
cave_entrance_ranger_kevin

Ranger Chris led us 250 feet down under the ground...
ranger_chris

That's the deepest I've ever been under ground.

I took a few pictures in the cave, but they keep it pretty dim and you're not allowed to use a flash. Here's one I lightened up a bit on the computer...
cave

Here's the historic entrance...
cave_entrance