The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

At one of Berlin’s oldest churches, visitors can place mosaic tiles to help restore a medieval mural.

How did a French journalist’s grave become the sexiest statue in the cemetery?

Stripes of human ashes cover a back lawn in the most sought-after burial grounds in Paris.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

This structure atop a craggy cliff in one of the most beautiful parks in Paris boasts an unbeatable view.

This massive library holds what was once the largest book collection in the world.

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

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

A surrealist timepiece by the artist of melting clocks.

A lone cannonball remains lodged in the walls of the Hotel de Sens as a sober reminder of a revolution.

Ghosts of France's colonial past.

The narrowest street in Paris.

Paris' linguistic guide to the international language of, yes, love.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

Notorious artist squat renovated into legal studios.

A simple plaque on the facade is the only reminder that the treaty ending the American Revolution was signed inside.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

This frog-themed restaurant was frequented by Picasso, Saint-Exupéry, and more.

This mural painted by Keith Haring was done without payment as a gift to entertain the children at the Hôpital Necker.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

The first green space constructed on an elevated viaduct.