Editor's note: Most cities would be delighted to have one or two UNESCO World Heritage Sites (New York has one, for example, Moscow has three). Barcelona has nine, making it easily the most Instagrammable city in Europe. From out-of-this-world architecture to city beaches to the largest football stadium in Europe (complete with its own museum), Barcelona is a multi-faceted city that delights shoppers, foodies, history buffs and photographers. If you haven't yet taken your first trip to Barcelona, start planning with a wallpaper from our gorgeous collection!