Eiffel Tower, Paris

The Eiffel Tower has surpassed 300 million #eiffeltower Instagram tags, making it the world's most photographed structure. Designed by Gustave Eiffel for the 1889 World's Fair, it now hosts 7 million visitors annually and is photographed from the Trocadero, from bateau mouches, and from the tower itself. The evening light show generates particularly viral content.