Massive volcano in the Andes is the farthest point from earth's center.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

One of Mexico's least-visited archaeological sites is tucked away inside a theme park.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

A house carved into a rock in the 1940s.

This southwest-styled home in Santa Fe claims to be the oldest house in America thanks to an ancient bit of foundation.

The oldest continuously occupied public building in the United States.

This highly decorated dam is one of Guanajuato's most unexpectedly beautiful public works.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

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

During its heyday, 72 one-ton buckets from this dredge bore into the Powder River excavating vast gold deposits.

An ancient Scottish rock formation said to be the gravesite of a giant remains ensconced in legend and intrigue.

After millennia of erosion by sand and churning water this Brazilian valley now looks like a lunar fantasy.

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

A series of labyrinths in the Nevada desert inspire meditation and calmness.

This huge dam across the Colorado River caused an armed standoff between two U.S. states.

The shop's owner has spent decades in the desert wearing nothing but a strategically placed sock.

This oasis-like spring in the Sonoran Desert is home to unique, endangered species.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

Rich red almandine gemstones are waiting inside the volcanic rock strewn across this eastern Nevada hillside.

The Jewish section of the famous Boothill Graveyard was abandoned for nearly 100 years.