The castles and forts were built and occupied at different times by traders from Portugal, Spain, Denmark, Sweden, Holland, Germany and Britain. IntegrityThe property contains all the significant remains of forts and castles along the coast. AuthenticityThe forts and castles were periodically altered, extended and modified to suit changing circumstances and new needs. As symbols of trade, and particularly the slave trade, they need to continue to reflect the way they were used. Also James Fort, Accra, and Fort William, Anomabu, are no longer in use as prisons and have been handed over to the GMMB.