Cape Coast Castle (Swedish: Carolusborg) is one of about forty "slave castles", or large commercial forts, built on the Gold Coast of West Africa (now Ghana) by European traders. It was originally a Portuguese "feitoria" or trading post, established in 1555, which they named Cabo Corso.

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 Atlantic slave trade. Other Ghanaian slave castles include Elmina Castle and Fort Christiansborg. They were used to hold enslaved Africans 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. Cape Coast Castle, along with other forts and castles in Ghana, are included on the UNESCO World Heritage List because of their testimony to the Atlantic gold and slave trades.