English: The Sierra Leone estuary became a focal point for trade and interaction between Africans and Europeans because of its exceptional harbor, starting in the mid-15th century. European ships were unable to land along much of the West African coast due to lack of safe anchorage. By contrast, the Sierra Leone estuary offers ideal anchorage for trading ships. Around 1672, the English established and fortified themselves at Bunce Island. By the mid-eighteenth century, Sierra Leone had become a major trading participant with Europe and the Americas. The image was acquired December 28, 2009, covers an area of 32x45km, and is located at 8.5 degrees north, 13 degrees west.