What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.

This titanic oil company sign is a reminder of the Americana boom of the 1970s and also its commoditization.

This bridge uses an inverted bowstring truss and is believed to be the only of its kind in the United States.

The largest ancient burial mound in Ohio.

A symbol for the opposition to nuclear power around the world.

Model Trains and Much More in Hamburg.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

Every equinox this Maya pyramid puts on a spooky ancient light show.

An exquisite collection of fairytale conveyances that puts most car museums to shame.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

As the Dead Sea continues to deplete, massive sinkholes open along its banks.

The world's largest occupied bat houses hold hundreds of thousands of flying mammals.

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

Deep scars on the earth left by the Ice Age.

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

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

A six-ton wedding present for the King of the Scots.

The fountain marks the area where hundreds of accused witches were burned at the stake.