Prince Henry of Portugal opened a school of navigation. It improved Portuguese navigation skills to such an extent that sailors and navigators were prepared to sail towards Africa and the Equator. Sailors and navigators had refused to sail anywhere near Africa and the Equator. They were petrified of the sea monsters and boiling water near the Equator. No sailors had ever sailed into the "Sea of Darkness". According to the Portuguese, the "Sea of Darkness" started at about 27 degrees north latitude. The School of Navigation sent fourteen expeditions into the Sea of Darkness and was instrumental in finding the sea route from Portugal towards the Indies.