progress at important landfalls. Also onboard were six Africans who had been kidnapped by Cão and taught Portuguese. Dias's plan was to drop them off at various points along the African coast so that they could testify to the grandeur of the Portuguese kingdom and make inquiries into the possible whereabouts of Prester John. The expedition sailed directly to the Congo, and from there proceeded more carefully down the African coast, often naming notable geographic features after saints that were honored on the Catholic Church’s calendar. When they weighed anchor at what today is Porto Alexandre, Angola, Dias left the supply ship behind so that it could re-provision them later, on their return voyage. By December, Dias had passed the farthest point reached by Cão, and on 8 December 1487 he arrived at the Golfo da Conceicão (modern-day Walvis Bay, Namibia). After making slow progress along the Namibian coast, the two ships turned southwest, away from land. Historians have debated whether this happened because they were driven offshore by a storm or because they were deliberately trying to find more favorable winds. Whatever its cause, the change of course brought them success: the ships traced a broad arc around the tip of Africa and, on 4 February 1488, after 30 days on the open ocean, they reached the continent’s southern cape and entered what would later become known as Mossel Bay. The ships continued east for a time and confirmed that the coast gradually trended to the northeast. Dias realized that they had accomplished Portugal's long-sought goal: they had rounded the southern cape of Africa. Dias's expedition reached its furthest point on 12 March 1488, when it anchored at Kwaaihoek, near the mouth of the Boesmans River—where they erected the Padrão de São Gregório. By then, the crew had become restless and was urging Dias to turn around. Supplies were low and the ships were battered. Although Dias wanted to continue, the rest of the officers unanimously favored returning to Portugal, so he agreed to turn back. On their return voyage, they sailed close enough to Africa’s southwestern coast to encounter the Cape of Good Hope for the first time in May 1488. Tradition has it that Dias originally named it the Cape of Storms (Cabo das Tormentas) and that King John II later renamed it the Cape of Good Hope (Cabo da Boa Esperança) because it symbolized the opening