Cape Coast Castle is one of about forty “slave castles”, or large commercial forts, built on the Gold Coast of West Africa by European traders. It was originally a Portuguese “feitoria” or trading post, established in 1555. However, in 1653 the Swedish Africa Company constructed a timber fort there.
It originally was a centre for the trade in timber and gold. It was later used in the trans-Atlantic slave trade. Other Ghanaian slave castles include Elmina Castle and Fort Christiansborg. They were used to hold slaves before they were loaded onto ships and sold in the Americas, especially the Caribbean. This “gate of no return” was the last stop before crossing the Atlantic Ocean. Wikipedia