A rare chance to get up close and personal with a 13-mile ribbon of ice near downtown Juneau.

Five candy-colored villages on the Italian Riviera.

There’s a secret bunker inside the Brooklyn Bridge, but the city won’t say where.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

If all members were present at the table, a sixth of the world's wealth would be under the same roof.

This simple Manhattan salt house is artfully shaped... well, like a giant granule of salt.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

The most confusing clock in New York.

Home to items never before seen by the public.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Cold war icon and onetime "hole" in the iron curtain.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Breathtaking and huge 430 year old maps of Italy.

Macabre astrological automaton clock dating to the late 1400s.

Long the exclusive domain of birds and vagabonds, this little-known Central Park peninsula is open to the public once more.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

These curious caverns have been home to mushrooms, gangsters, and disco.

Secret hideaway for an alternative beach experience.

This iconic water tower and failed bandstand is open for panoramic views once a year.