The Eiffel Tower, Paris, 1914
If there ever was a building that was synonymous to architectural marvels. 1914 was the year that marked 25 years of the completion of this tower. While this structure is primarily known for its beauty, it also served an important purpose in World War I which broke out in the same year as this picture was taken. A radio transmitter located in the tower jammed German radio communications, seriously hindering their advance on Paris and contributing to the Allied victory at the First Battle of the Marne.