Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Historians and hobbyists head to this former French outpost for the annual Feast of the Hunters' Moon.

Purdue students would lean over this iron fence to skirt campus rules against smoking and courting.

This statue honors the author's groundbreaking family story.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

A blend of sporting history mixed with childhood nostalgia await visitors to this museum.

On the summer solstice each year, shadows align with a 14,000 square foot painting to reveal a secret message.

Outsider art or homage to aliens?

Special tunnels built so that frogs won't be killed when crossing the highway.

Seven ceramic sculptures are scattered around this California college campus.

Each summer, the migratory bats living beneath the bypass form "batnadoes" at dusk.

This museum boasts the ninth-largest collection of insects in North America.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

This unacceptably tall building was the real reason for Washington, D.C.'s skyscraper ban.

A rotating cast of guys and dolls in front of a Washington, D.C. building.

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

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

Every equinox this Maya pyramid puts on a spooky ancient light show.