Why were Europeans first interested in exploring Africa

Prince Henry "The navigator" of Portugal sent expeditions south along the west coast of Africa looking for a sea route to the Spice Islands and India. Vasco Da Gama was the first to reach the southern tip. Some settlements were established along the way along the African coast, notably in Angola and just past the Cape of Good Hope. Later, Africa was of interest to many other European countries as a source of slaves, and for mining and agriculture.