This photograph is of early 1907 vintage for the 1883 Cook 4-4-0 is numbered on the headlight 503.  The 500 series was later applied to the small ex French 0-6-0Ts.  The flat cars have low serial numbers. The locomotive still has pin couplers.  The location seems to be in a settled area for there is a small grandstand and playing field behind the trestle.  This would suggest a location near Mindi on the relocation to the new Gatun station.