A 16th-century Andalusian palace.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

This ancient Roman cistern has been the source of many legends throughout the centuries.

The ruins of an ancient stadium that hosted gripping chariot and horse races.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

Across Valencia lie the remains of three ancient fortifications built centuries apart: a Roman enclosure, an Islamic expansion, and a medieval Christian wall.

The most elaborate of 12 medieval arched doorways to the old city of Burgos.

For more than half a millennia, this automaton has rung an hourly bell.

Gustave Eiffel's masterpiece until the Eiffel Tower was built.

A small but charming botanical garden that contains many exotic plant species.

This historic streetcar system has been running since the 19th-century.

A hidden three-foot-wide house separates these two regal churches.

An icon of the city, this chapel features an amazing dome ceiling and offers panoramic views.

An accidental trick of light casts the perfect shadow of a pilgrim of the Camino de Santiago against the cathedral wall.

This enormous censer uses a pulley system installed over 400 years ago.

This pink watchtower served as the seat of the Greek government after independence from the Turks.

A hilltop monastery on the Greek island of Hydra.

The site where the summer solstice helped ancient Greeks sync the lunar and solar calendars.

These caves secretly held national treasures during World War II.

Rest stops along this pathway offer some of the best views of the Acropolis of Athens.

The world's oldest map of the holy land gives us a fragmented glimpse of the layout of biblical nations.

An ancient capital city that dates back 3,000 years and harbors many surprises.

Come for the whole sides of slow-roasted lamb, stay for the regional Kurdish specialties.

Taking the subway here means doing so over a bridge located in the middle of an estuary.