A handful of books that give Portobelo — and the Spanish colonial world it was born into — real depth.
Black Flags, Blue Waters by Eric Jay Dolin (2018) covers the golden age of Atlantic piracy with particular attention to the raids on Portobelo. Henry Morgan's audacious 1668 assault on the town, which he took with a fraction of the defending garrison's strength, is one of the set pieces of the book. Dolin is a clear and vivid popular historian, and this is the most accessible account of the pirate era in the Caribbean.
The Sack of Panamá by Peter Earle (1981) reconstructs Morgan's subsequent and even more ambitious campaign — the overland crossing of the isthmus and the destruction of Old Panamá City in 1671. Portobelo was the starting point of that march. Earle had access to Spanish archives and brings a rare bilingual perspective to events that are usually told entirely from the English side.
Open Veins of Latin America by Eduardo Galeano (1971) is the essential counter-narrative to the heroic stories of Spanish exploration. Galeano traces the extraction of silver from Potosí through exactly the route that passed through Portobelo — across the isthmus on muleback, loaded onto galleons in this bay, sent to Seville to finance European wars. It is a polemical book, not a neutral one, but no other work makes the human cost of the treasure fleets as visceral.
General History of the Indies by Gonzalo Fernández de Oviedo y Valdés (16th century) is a primary source rather than popular reading, but excerpts are widely available in translation. Oviedo sailed these waters himself and his chronicles of the early colonial Caribbean — the harbours, the indigenous peoples, the violence of conquest — are irreplaceable. The sections on the Panamanian coast describe a world that Portobelo's ruins still faintly echo.