Vintage Postcard 1900s Miraflores Locks Construction View Canal Panama City. This original antique postcard features an aerial view of the construction of the Miraflores Locks in Panama City during the early 1900s. The lithograph print captures the bustling community life of the Isthmus of Panama during the construction of the Panama Canal. The postcard is made of sturdy cardboard with a divided back and measures standard size (140 x 89 mm). This vintage postcard is a must-have for collectors of topographical postcards and those interested in the history of the construction of the Panama Canal. The postcard is in excellent condition and has not been posted.