Castilla de Oro or del Oro (Spanish: [kasˈtiʎa ðe ˈoɾo]) was the name given by the Spanish settlers at the beginning of the 16th century to the Central American territories from the Gulf of Urabá, near today's Colombian-Panamanian border, to the Belén River.
Beyond that river, the region was known as Veragua, and was disputed by the Spanish crown along with the Columbus family.
The name "Castilla de Oro" was made official in May 1513 by King Ferdinand II of Aragon, then regent of the Crown of Castile.
After Vasco Núñez de Balboa's discovery of the Pacific Ocean, Castilla de Oro's jurisdiction was broadened to include the Pacific coasts of Panama, Costa Rica, and Nicaragua.
In 1537, once the conflict between the crown and the Columbus family was settled, Castilla de Oro was split up, divided by the Duchy of Veragua.