Gamboa is located on a sharp bend of the Chagres River at the point which feeds Lake Gatun. Just south of Gamboa, Lake Gatun and the Chagres meet the Culebra Cut (Gaillard Cut) where the Canal cuts through the Continental Divide. Thus, though Gamboa is closer to the Pacific side of Panama, its watershed is on the Atlantic side. A single lane iron and wood bridge crosses the Chagres and is the only road access to Gamboa. This bridge is still in use today. Vehicles waiting to pass over the bridge must wait for a stoplight to enter the bridge, since it is only capable of providing space for one lane of traffic at a time. In December 2010 this bridge was the site of massive flooding and huge floating islands passing under the bridge, with trees violently hitting it, which led to the temporary closure of the Panama Canal.