Site of the greatest known waterfall that ever existed.

This scenic gorge is named after one of the most famous Bigfoot attacks in pseudohistory.

This remarkable collection devoted to the study of fish includes 1 million preserved specimens from all around the world.

An obscure waterfall that looks like something out of a fantasy novel.

Rustic natural hot springs in the deciduous rain forest.

Stroll through a wonderland of stupendous moss-covered trees.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

The highest point in Virginia can only be reached by passing through ponies and flowers.

This museum devoted to the gothic author holds such interesting ephemera as his socks and walking stick.

This set of three large, volcanic hot springs is a favorite haunt for intrepid divers.

A tunnel with windows, so you don't miss out on the impressive views.

This geothermal hot spring hides beneath a slowly growing mineral dome.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.

Steep canyon walls hide a forested oasis in the West Texas desert.

This sacred cavern, 400 feet deep, is home to millions of bats and an ancient burial ground.

A Texas cave network is home to some of the world's most spectacular-looking and bizarrely named mineral formations.

A taste of Middle Earth, in the middle of the Bayou City.

Continuing the tradition of the dime museum in style.

An emerald-green grotto just a short trip from Austin.

This park offers a variety of sights and activities including trail rides and buffalo sightings.

In one of America’s oldest mountain ranges, a long-awaited section of a scenic highway is now open to the public.

Mile-long cave system near Great Smoky Mountains.

More than five miles of underground passageways.