A whimsical monument deep in this park commemorates the groups that helped build it.

Along the Palisades skyline are the ruins of a large mansion built in 1911 and demolished in the 1930s.

In the power of this waterfall, Alexander Hamilton saw the potential for industry.

An Irish Memorial commemorating those who perished due to potato blight.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

One of Philadelphia's largest murals resides hidden under this bridge.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The origin of this mechanical boy was a mystery until he revealed his maker by writing it in perfect cursive.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

Venture into the past with an unlisted exhibit hall featuring extinct birds.

Sip creative cocktails in the former vault of the Riggs Bank.

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

This restaurant has been a haven for D.C.'s LGBTQ community since the 1950s.

A museum dedicated to the mysterious cryptid.

In the middle of a suburban Denver neighborhood is a cave that once provided solace for a prominent Ute chief and his family.

A prehistoric rock shelter that's literally in someone's backyard.

Explore some of the most unique vehicles in history along with a cast of unsettling mannequins.

A technicolor place of worship for Elevationists.

A multiversal transit station located right below a highway interchange.

Overlooking the Colorado Convention Center is this giant sculpture made from thousands of triangles.

A 140-year-old castle with underground caves hidden in San Francisco.

Part mural and part sculpture, this work of art sits in the middle of the Promenade, as if swimming in a river of asphalt towards the ocean.

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.