Mammoth Cave, located in Kentucky, is the world's longest, known underground cave system. It's been called a "grand, gloomy and peculiar place," but its vast chambers and complex labyrinths have earned its name - Mammoth! But seeing this amazing set of caves is not the only thing you can do at Mammoth Cave. There are also approximately 90 miles of trails available for hiking, biking and horse riding, and also extensive camping, canoeing and kayaking locations available! I've been on two different tours at Mammoth Cave: the Historic Tour and the Domes & Dripstones Tour. The Historic Tour is to walk for 2 miles inside a very dry cave, just rocks and rocks and more rocks. Not really anything wortt photographing, but a cool history to hear none the less! There are quite a few tight squeezes and small staircases, so be aware of that! The Domes & Dripstones Tour is just like the Historic Tour, but at the end of the tour, there is a wet cave where you can see a bit of stalactite and stalagmite formation, which is the big reason anyone who loves caving might want to see! If you have to choose just one tour, go with this one. The coolest part about these 400 miles of underground caves, that have been explored for over 5,000 years is not just that they're so large. It's that the exploration is still incomplete! Who knows what else will be found? The caves are open for tours year round, but call or check their website for a full schedule and details on how to get to the caves. ---Phone no. 270-758-2180 ---Website. www.nps.gov/maca As far as hiking trails, there are so many available, including: Big Hollow Trail - 8 mi Mammoth Cave Horse Trails - 60 mi Munfordville to Dennison Ferry - 22 mi Dennison Ferry to Green River Ferry - 7.5 mi Green River Ferry to Houchin Ferry - 12 mi Mammoth Cave Railroad Bike & Hike - 10 mi Heritage Trail - 0.3 mi River Styx Spring - 0.6 mi Mammoth Dome Trail - 2 mi Green River Bluffs Trail - 1.1 mi Echo River Trail - 2.2 mi Echo River Spring Trail - 0.4 mi Dixon Cave Trail - 1.2 mi Campground Trail - 0.5 mi Turnhole Bend Nature Trail - 1 mi Sloan's Crossing Pond Trail - 0.4 mi Sand Cave Trail - 0.1 mi Cedar Sink Trail - 0.8 mi White Oak Trail - 2.7 mi Wet Prong Trail - 4.9 mi Wet Prong-McCoy Hollow Trail - 0.4 mi Turnhole Bend Trail - 3.2 mi Sal Hollow Trail - 8.7 mi Raymer Hollow Trail - 4.7 mi McCoy Hollow Trail - 6.3 mi First Creek Hollow Trail - 6.7 mi Collie Ridge Trail - 4.3 mi Buffalo Trail - 4 mi Blair Spring Hollow Trail - 1.2 mi Click the names of any of those trails here (http://www.kentuckytourism.com/outdoor-adventure/attraction/caving/mammoth-cave-national-park/529/) to find out more about each of these trails, and add on some hiking to your cave visit!