The Canal was begun working on by France in 1881, but after that was taken over by the United States in 1904, and opened on August 15, 1914. It is considered as one of the largest and most difficult engineering projects ever undertaken.
These are photos of an early crossing of the Panama Canal. The ship is the S. S. Panama, the first excursion ship to go through the Panama Canal on Feb. 7, 1915. Most of the buildings still seem to be under construction. These appear to be the three Gatun locks.
via Richard