Geography and disease shape the bullion route

Moving treasure through Acapulco and Veracruz requires extra sea and land transport, repeated loading, and more opportunities for theft. In wartime it can nevertheless be safer because an attacker needs much longer to reach the Pacific route. Porto Bello remains attractive because catching or containing the treasure fleet there could dictate Spanish choices at the shortest crossing. Its tropical disease environment makes prolonged stationing dangerous for the blockader. Earlier raids by Drake had also encouraged Spain to relocate and fortify the bullion port, so geography favors speed while experience favors defense.