Oldest synagogue in the United States.

The oldest still-operating tavern in the United States was once owned by a pirate.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

An ear-piercing buzzer calls lawmakers to a vote with a series of long and short rings to form coded messages.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

An easily overlooked memorial to a Ukrainian famine-genocide that killed over 4 million people.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

A towering Art Deco movie palace made to look like a Mayan temple.

France's most famous cemetery, with some of its most curious tombs.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Climb inside an iron crystal magnified 165 billion times its normal size.

The ancient tomb acts as a calendar that keeps perfect time.

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

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

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

This ancient Irish tower could easily have stood in for Rapunzel's prison.

A hugely vast Irish landscape of barren rock that stretches for miles.

Originally used to sell brandy, the bull-shaped billboard became an iconic symbol of Spain.

Home with Gothic windows featured in a famous painting.

This unacceptably tall building was the real reason for Washington, D.C.'s skyscraper ban.

Washington's iconic carousel has a nice piece of Civil Rights history.

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