A tiny church on a man-made island in the Adriatic.

A curious cave church carved into the face of a cliff.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

The only quarter of the Old City not dedicated to a major world religion.

This unassuming oasis elevated just above the busy streets of Jerusalem offers one of the best views of the Old City.

This clock is an architectural flourish that stands out as a landmark among a unique Israeli German community.

The maze-like transportation hub contains abandoned areas, derelict stores, and a resident bat colony.

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

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

Deep in the Negev Desert, the world's tallest solar tower looks like a sight straight out of science fiction.

A massive, heart-shaped, wind-carved crater in the middle of the Israeli desert.

Squeezing inside this deep, narrow canyon reveals a festival of desert colors.

Hundreds of hidden passageways weave through the old quarters of Lyon.

For hundreds of years, automatons moving to metallic music have been marking the passage of time.

Lyon's miniature version of the Eiffel Tower was built as a statement in support of French secularism.

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

Explore this medieval cathedral by trying to spot all the malevolent monsters hiding in its beautifully colored windows.

A memorial to the soldiers who died in the bloody battles to control Verdun in World War I.

Historic medieval fortified city in southwest France.

The world's largest solar furnace uses 10,000 mirrors to concentrate the sun's rays to generate power.

Natural mummies hidden in the crypt of a medieval French church.

A Gothic cathedral created from volcanic rocks.

Terrifically morbid cemetary and site of famous Paracelsus' grave.

American soldiers discovered Europe's best one-liner at the end of World War II.