On his return journey south, still with only the larger "Santiago" and a reduced crew, Heceta discovered a large bay penetrating far inland. He was the first European to sight the mouth of the Columbia River. He tried to sail in but the strong currents prevented it, even under a full press of sails. His crew was so reduced that they could not handle the anchor so he could not easily wait for better conditions. He wrote that the seething currents led him to believe it was the mouth of a great river or a passage to another sea. Later he guessed it to be the Strait of Juan de Fuca. He named the entrance bay "Bahia de la Asunciõn" and produced a map of what he could discern from outside the Columbia Bar. Later Spanish maps often showed the Columbia River's estuary with the name "Entrada de Hezeta", "Rio de San Roque", and other similar variants.