In the 14th and the 15th centuries, the shipyards of Porto contributed to the development of the Portuguese fleet. In 1415 Henry the Navigator, son of João I, left from Porto to invade the Muslim port of Ceuta in northern Morocco. This expedition led to the exploratory voyages that he later sent down the coast of Africa. Portuenses are referred to this day as "tripeiros", in reference to the fact that higher quality meat would be loaded onto ships to feed sailors, while off-cuts and by-products such as tripe would be left behind and eaten by the citizens of Porto. Tripe remains a culturally important dish in modern-day Porto.