During the Spanish-colonial era, the Costa Arriba became one of the most strategically important areas in the entire Spanish Empire. It was here that most of the incredible treasure of the Incas was brought after being shipped up from South America.

All that wealth made the Caribbean coast a target of pirates and buccaneers for hundreds of years. The Spanish fortresses were constantly under siege and were captured several times.

Entering Portobelo from the west, the first Spanish structure you’ll encounter is Castillo Santiago de la Gloria, on the left side of the road. It’s the last incarnation of a fort that was built, destroyed, rebuilt, and tinkered with for more than 150 years and never ended up defending the town particularly well. These ruins date from 1753.

In the town itself is Castillo San Gerónimo, which dates from the same period. The nearby Customs House, the Real Aduana de Portobelo, was restored in February 1998 by the Spanish government. If you hadn’t seen its state before the restoration, you might have a hard time figuring out what was done to it.

Still, the place has been through a lot: Originally built in or around 1630, it was seriously damaged in a 1744 attack, then rebuilt, then damaged again in an 1882 earthquake. Just a couple of walls were left standing before the restoration.

The little museum inside the building has recently been spiffed up with a few modern displays and a film on the history of the area. There’s a small model of Portobelo’s fortifications just outside the entrance. On the other side of the model is a second room where one can see a bit of the original foundation, but “exhibits” consist mainly of a few old tools, cannonballs, and mortars. There are also replicas of pre-Colombian tools and weapons mixed in with a few pieces of real pottery shards.

Admission to the museum (8 a.m.–4 p.m. Mon.–Fri., 8:30 a.m.–3 p.m. Sat.–Sun.) and to the neighboring Museo del Cristo Negro de Portobelo is US$1 for adults, US$0.25 for children. The price includes a guided tour of the displays, though the guides speak only Spanish.