On the Pacific side of the Panama Canal  it takes two sets of locks to raise or lower ships 85 feet (26 meters). Gatún Locks (visiting hours: 9 A.M.–4 P.M. daily), on the Caribbean side west of Colón , do the job by themselves. Each lock chamber is the same size as those on the Pacific—1,000 by 110 feet (almost 305 by 34 meters)—but there are three pairs of them on this side. That makes Gatún Locks absolutely massive, a little less than a mile (more than 1.5 kilometers) from end to end. It’s an impressive sight.
Note: As dramatic as the locks are, most visitors based on the Pacific side of the isthmus are satisfied with seeing Miraflores  and perhaps Pedro Miguel  without making a special trip just to see these.
An observation platform up a long flight of stairs gives an excellent view of the locks, the Caribbean entrance to the canal, and Lago Gatún . There’s another observation spot downstairs. It has a small scale model of the entire canal. Bathrooms for tourists are in the building behind the model.
The number of tourists visiting the locks is increasing, but free bilingual talks, like the ones offered at Miraflores, are still sporadic here. The best bet to catch a talk is when a cruise ship disgorges its passengers for a tour.
If time and transportation allow, take a quick spin through the townsite of Gatún, next to the locks. The area is still under control of the Panama Canal Authority, and is well maintained—the grass is neatly cut, and the old houses and employee facilities are still in pretty good shape. A visit will give a taste of what life in the old Canal Zone looked like. However, canal expansion is bringing rapid change even to this area. Its days are numbered.