From the 15th to the 19th century, it was the largest slave-trading centre on the African coast.The House of Slaves was built in 1776 by the Dutch, the last surviving slave house in Gorée; the earliest date back to 1536 and were built by Portuguese.A small house contained between 150 and 200 slaves, who had to wait for very long periods - up to three months - before being carried away on board ship.