This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

This French chateau is home to the world’s largest private collection of fighter jets.

A symbol of friendship between the mountainous regions of Switzerland and Bhutan.

Medieval irrigation channels built into the sides of mountains provided Valais with water for hundreds of years.

Over 3km of caverns and caves at the Switzerland-France border contain the largest underground river in Central Europe.

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

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

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

A once drab public housing estate is transformed into a colorful gallery of trompe l’oeil murals.

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

The experimental test tracks of a retro-futuristic monorail still stand in the French countryside.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.