A view along the bay-facing wall of the main Portobelo fort 'Fuerte san Jeronimo'. The bay of Portobelo is stunning, narrow entrance, wide bay, surrounded by mountains. There were several forts built around Portobelo beginning in 1601. These forts were constructed of cut-coral blocks, which is clearly evident on close inspections. Coral is tough, light and easily cut with a saw. Much of the coral for these and the other forts was taken for construction of the Panama Canal by the Americans.

As can be seen here, these were substantial construction projects for their day.