The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Hanging over one of Japan's "hidden valleys," these vine bridges must be remade every three years.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

No one knows how this Pacific Northwest spruce tree came to have so many trunks.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

A fiery crater has been burning in the Karakum Desert since 1971.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

Quite simply the largest tree in the world (by volume).

Oregon's unexpected high desert, displaying layers of time in a colorful show.

The longest hedge maze in the world.

The scuba diving training facility was named for the steam that rises from the cave's chimney.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

It's not hard to see why the historic Peabody Conservatory of Music's library has been described as a "cathedral of books."

A museum dedicated to the alleged Roswell Incident.

This massive wooden building contains a giant Buddha, healing pillars, and tame deer wandering the grounds.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

The magical, mossy forest that inspired Princess Mononoke.

A curious collection dedicated to human and animal anatomy and pathology.