The grand marble structure next to the White House is Andrew Carnegie's temple to Pan-American diplomacy.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Look closely and you’ll notice that the color changes a third of the way up the tower.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Washington's iconic carousel has a nice piece of Civil Rights history.

The "lovely red Vega" of the legendary record-settling pilot.

A rugged lava field dotted with molds of the ancient pines that were growing when the volcano erupted.

A vertically floating hemlock controls the waves and weather at Crater Lake.

Portlandia is the second-largest copper repoussé statue in the United States.

This extravagant Art Nouveau rest stop features a million-dollar view of the Columbia River.

Despite a legend that says this highest peak in Oregon was climbed in high heels scores of people have died on its slopes.

You might know it as the Overlook Hotel, but the inside is not going to be familiar.

This 15-foot tall obelisk commemorating the Philadelphia-Baltimore railroad connection sat neglected for over a century.

A tiny, unmarked beer and whiskey bar above an Ethiopian restaurant in West Philly fails to conceal live bluegrass.

This amazing ancient cave was kept secret for seven years to protect it from the public.

"Girl in a Wetsuit" is what happens when a sculptor has to find a way around a 100 year old copyright.

This historic rec center in the heart of Israel is a bastion of peace and togetherness.

An ancient underground cultic temple where sunlight penetrates on the summer solstice.

The singer, actor, and activist lived here during his final years, and now it’s a museum dedicated to his legacy.

Alexander Hamilton’s creation caused quite a bit of controversy.

The seat of Buffalo government is a gorgeous Art Deco palace.

These elusive, isolated rodents evolved into a distinct, locally iconic subspecies.

The remnants of a creative early method of wildfire prevention.

The fifth-longest natural arch in the world, and the longest outside China.