A mysterious shape catches the eye in this 16th-century painting.

These docile dragons are ideal inhabitants for the conservatory greenhouses.

The rose garden in Regent's Park where Pongo and Perdita met for the first time in Disney's "101 Dalmatians."

Eighty million natural history specimens call this gargantuan museum home.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Scars of this building's past life as a violent prison still cover its walls.

Where commuters walk through remnants of an ancient Greek necropolis.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

Legend says this sacred tree was a gift from goddess Athena.

A sharp sculpture made of thousands of pieces of jagged glass.

An ancient octagonal weather station named for the eight Greek gods of wind.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

In the waters outside Helsinki, a tiny island once used as a military outpost now welcomes visitors.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

An abstract monument to a symphonic composer.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

View the ancient remains of buildings and the ancient "River of Hades" before hopping on a train.