The wreckage of a tragic plane crash is on display at this museum devoted to a famous Italian conspiracy.

The sinister ruins of one of the worst dam failures of the 20th century lie in this astonishing alpine setting.

This work of engineering is imbued with elegance and ingeniousness.

A tower-like theater in the Swiss Alps built to withstand the high winds and avalanches of the mountain pass.

A second generation sun-powered marvel lights up the night.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Romans built the world's tallest artificial waterfall in 271 BC.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

Singapore's landscaping project is home to 18 incredible Supertrees.

Look closely and you’ll notice that the color changes a third of the way up the tower.

A building so large that it has its own weather.

Poland's oldest salt mine has nearly everything one needs to live underground forever.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

According to the Guanches, the aboriginal people of the Canary Islands, the king of evil lives inside this volcano.

Single runway interrupted by a busy road that cuts across its middle.

Nobles would stage mock naval battles on this large lake at the Royal Palace of Caserta.

The only visible remains of this ancient Greek underground temple is its roof protruding from the earth.

Also known as the Temple of Poseidon, this is one of the best-preserved Greek temples in the world.

This scenic fortress dates back at least 2,400 years to the time of Magna Graecia.

People have been living in the cave houses on this Italian hillside since the Neolithic era.