Thousands of ships transit the Panama Canal every year, but few imagine what happens when one of its locks needs to be repaired. The Pedro Miguel locks, one of the original structures built by the United States over 110 years ago, were partially emptied this week to allow for refurbishment work to take place. For five days, the west lane of the Pedro Miguel locks was closed to ship transits while dozens of technicians descended into the depths of the dry chamber to repair, adjust, and seal parts of it. (AP Video: Matías Delacroix)