This massive circular sculpture may not be a portal to other worlds, but it does inspire the mind to imagine them.

This inexpensive lodging house was once a prison notorious for its inhumane practices.

Now a public art piece, this curious metal feature originally advertised a tinsmith's services.

Louise Bourgeois' 30-foot-tall steel spider sculpture.

The mastermind behind this palatial hotel perished on the Titanic weeks before its grand opening.

The first post office in Toronto still operates today, complete with quill pens and ink for writing letters.

This Niagara Falls tourist trap is a world bright with neon and curiosities that will inspire love, hate, or a mixture of both.

Michigan's oldest operating hotel predates the state itself.

Largest magic museum in the United States with more than half a million pieces of memorabilia.

A herd of roughly 250 American bison roam these plains.

Indiana’s largest prehistoric earthwork, aligned with the solstices.

A monument marks the beginning of the longest north-south road in the United States.

This lovely, if imposing, piece of Canadian gothic is possibly the most photographed hotel in the world.

One of the largest collections of merchandise from the famous British sci-fi show can be found smack in the middle of Indiana.

A five-square-mile slice of Spain on the Mediterranean coast of North Africa.

The facade of this 16th-century building is decorated with carvings of 300 seashells.

This enormous censer uses a pulley system installed over 400 years ago.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

An overlooked memorial honoring the local Washington residents who died in World War I.

A gift from Japan, 17th-century lantern stands among the cherry trees at D.C.'s Tidal Basin.

The only National Monument ever to go missing for nearly 50 years then resurface in a dump.

Outside the Department of Transportation, a collection of artifacts honors the history of how we get around.

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

This Ohio cemetery is home to the remains of many Confederate officers and soldiers who were once held nearby as prisoners of war.