The construction of the locks began with the first concrete laid at Gatun, on August 24, 1909, by the Philadelphia-based company Day & Zimmermann. The Gatun locks are built into a cut made in a hill bordering the lake, which required the excavation of 3,800,000 cubic meters of material, mostly rock. The locks themselves were made of 1,564,000m3 of concrete.
The gates are of enormous size, ranging from 14.33 to 24.99 meters high, depending on position, and are 2.13 meters thick. The heaviest leaves weigh 662t the hinges themselves each weigh 16.7t . Each gate has two leaves, 19.81m wide, which close to a “V” shape with the point upstream.
The original gate machinery consisted of a huge drive wheel, powered by an electric motor, to which was attached a connecting rod, which in turn attached to the middle of the gate. The seagoing tug Gatun, made the first trial lockage of Gatun Locks on September 26, 1913.