This bleach-white graveyard overlooking the ocean is accessed through a tunnel.

This tiny home was originally a narrow alleyway.

The crumbling remnants of this 19th-century quarantine hospital hint at the touristy island's darker past.

This small fort played a huge role defending Puerto Rico’s capital city.

On a clear day, you can see all the way to the Virgin Islands from the top of this observation tower built in the 1960s.

On this Puerto Rican island, many abandoned naval ammunition bunkers sit open while a few have been padlocked by locals as personal storage.

The world's brightest bioluminescent bay.

Hundreds of fiberglass structures line the side of the road in the middle of nowhere.

This Transylvania County city is home to a rare white squirrel population that is descended from an escaped carnival animal.

The author's beautiful and historic home is also a fully functioning goat farm.

This posh mansion began as a family's estate and ended as the site of a murder ripped from the pages of a pulp novel.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

Home to the deepest rift anywhere on Earth.

A volcanic tunnel illuminated by natural skylights offers a shaded respite from the desert sun.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

This historic home of the shag is keeping a Southern dance tradition going strong.

Divinely-inspired village houses 6,000 dolls, plus strange and lovely outsider art.

This handcrafted, old western-style town is filled with deserted cars, retired movie props, and other forms of Americana.

The final resting place of two (or three) presidents, one vampire, and 18,000 Confederate soldiers.

Amphibious mascots display a quirkier side to this luxury hotel's rich history.

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

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."