A series of waterfalls so massive they straddle the border of Argentina and Brazil.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

Massive stele returned to Ethiopia after 70 years in Rome.

An otherworldly restaurant perched on the edge of a jagged cliff next to a medieval holy city.

The massive cave church of Cairo's Zabbaleen community is one of the largest Christian churches in the Middle East.

Even King Tut was intrigued by the glass of the Great Sand Sea.

An endless sea of white conical domes.

An ancient city exhumed from the depths of the ocean.

Mount Nyiragongo has erupted at least 34 times since 1882 and is home to the world's largest lava lake.

Spanning over 10,000 square miles, this ancient salt pan is one of the largest on the planet.

There is only one place in the world where the corners of four nations come together.

Wondrous stalactites house thousands of bats in these African caves.

Did Gustav Eiffel design this enigmatic metal building?

The world's only museum devoted to the wonders of fluorescence.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A giant gun barrel in Barbados that once hoped to shoot outer space with science.

Giant pigeon houses packed into city streets in Egypt.

The largest known Ancient Egyptian obelisk.

Brightly painted boulders scattered throughout the Sinai Desert.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

This artificial archipelago was supposed to resemble a map of the world.

"Excuse me sir, your submarine is blocking my building."

Crawl through the hole in the middle of this stone to break off a bad relationship or initiate a good one.

This bridge is so steep it looks like a rollercoaster.