Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

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

This towering church is home to a world-famous organ and a treasure trove of medieval art.

Home to 23 voluptuous and instantly lovable sculptures by one of Latin America's most celebrated artists.

Two identical statues by Fernando Botero, one blown to pieces in a terrorist bombing, the other donated as a gift for peace.

The colonial city's social history is reflected in its fanciful door knockers.

An unusual and beautiful form of mass transit serves the city's steepest neighborhoods.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

While the U.S. and Soviet Union were engaged in a space race, Poland built a UFO on the ground.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

This 700-year-old structure is one of the most unique architectural and historic monuments in Gdańsk.

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

Swedish skyscraper with a 90° twist.

This chimerical bridge/tunnel appears to dead end right into the sea.

Breathtaking and huge 430 year old maps of Italy.

The biblical sculpture honors those who lost their lives, homes and communities to the Chernobyl disaster.

This derelict superstructure was a very important warning system for the Soviet military.

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

This attraction was abandoned after the Chornobyl disaster.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.