The Guardian of Tallinn.

The oldest continuously operating pharmacy in Europe.

During the Soviet era, the spire of this longstanding church was used as a radio transmission tower.

The door to the museum holds a unique artifact from the Finnish Civil War.

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

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

This church also serves as a lighthouse complete with a beacon.

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

Stockholm's narrowest alley is barely over two feet wide.

Copenhagen's celebrated theme park and gardens.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

A 200-year-old collection of medical paraphernalia in a historic house.

Despite the groans of archaeologists, this astounding groups of Bronze Age petroglyphs have been painted red for tourists.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

A galley-shaped memorial to the prisoners of an infamous fortress.

This clifftop arch is a natural stunner.

A mushroom-shaped outcropping that has come to be the symbol for an entire town.

A snow-white church overlooking the wonderful Tyrrhenian Sea.

The largest hewn stone in history.

These ancient ruins hide in plain sight next to a dessert shop.

Giant marble phalluses on the sacred island of antiquity.

Replicas of Apollo's leonine stone guard cats still line a sacred row in Greece.

A Bronze age settlement on the Greek island of Santorini might have been the inspiration for Plato's Atlantis.

This famous archeological mystery may be an ancient example of movable type.