 Gold and silver were brought by ship from South America, hauled across the Isthmus, and loaded aboard ships for Spain.The route became known as the Camino Real de Portobelo, or Royal Road of Portobelo, although it was more commonly known as (Royal Road of the Crosses) because the road led to the TOWN of Venta Cruces located on the Rio Chagres.Panama was part of the Spanish empire for nearly 300 years, from 1538 to 1821.