The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

Iconic rock formations that allow for exploration during high or low tide.

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

Memorializing an American tragedy of massive proportions.

The first North American landing spot for James Cook on his third voyage of discovery in the Pacific.

Go inside the house that inspired L. M. Montgomery to create one of literature's most beloved heroines.

Rusty red sands line the shores of this Canadian Province.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

A hugely vast Irish landscape of barren rock that stretches for miles.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

The last bastion of Roman presence north of the Alps looms over a German town.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Three and a half miles of cliffs, rocky beaches, Gilded Age mansions and 40 Steps to nowhere in particular.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

The largest stone circle in the world has ended up bringing up more questions than it has answered.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.

Florida might be at its most surreal in this museum devoted to the famed Spanish artist.

The curiosities and wonders of pharmacy in a delightful historic building.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

An angular maze of concrete in Grand Rapids acts both as public art and as a staircase for fish traveling upstream.

Holding multiple historical boats and an entire 19th century village, this New England attraction is the largest maritime museum in the world.