Rebuilt remains of a temple to Roman god Mithras.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Eighty million natural history specimens call this gargantuan museum home.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

These relics of the city's past now exist as a prominent modern feature.

Designed as a reminder of one of the darkest moments in Austrian history.

A gift from Emperor Franz Joseph I to his wife.

The first modernist church in Europe.

This grand manse has been transformed into a museum devoted to one of the founders of Fantastic Realism.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

The solemn exterior conceals an opulent interior of this 17th century church.

An exquisite Baroque church in Vienna's old town.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.

Dine amidst exotic plants at this former royal greenhouse.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

A relic of World War I that now exist as a piece of public art.

A bronze woman in a stylized dress honors a courageous politician.

A plaque bearing the names of those who dedicated themselves to protecting Budapest's Jewish population during World War II.

A highly-criticized monument in Budapest has become the site of a makeshift Holocaust memorial.

This memorial to a murdered empress took 20 years to design, then spent 30 years hidden away in storage.