Visit the Spanish ruins of Fuerte Lorenzo, declared a Unesco World Heritage Site in 1980, is perched at the mouth of the Río Chagres on a promontory west of the canal. Despite its violent history, much of San Lorenzo is well preserved, including the moat, the cannons and the The fort also commands a wide view of the river and bay far below, which was one of the reasons the Spanish chose to fortify the site.Gatun Locks and Gatun Lake, located 10km south of Colón, raise southbound ships 29.5m from Caribbean waters to Lago Gatún, the size of them is mind-boggling. Chosen excursion available subject to minimal number of participants.