This park, covering 360 sequare kilometres, is a triptych protecting forested coastal mountains, 70 km of shoreline, and Caribbean waters that sustain precious mangroves and coral reefs. It encloses Spanish colonial ruins dating back five centuries to when the town of Portobelo was the most important treasure port in the Americas.

The eighteenth century fortress ruins seen today are second generation and smaller than their precursor, since they protected a port that has lost its importance as trade waned. Built into the rugged hills on each side of the bay, their watchtowers peek out from between palms atop walls slowly yielding to the encroaching jungle.