Nanaimo Harbour, also known as the Port of Nanaimo, is a natural harbour on the east coast of Vancouver Island, British Columbia, Canada. The City of Nanaimo runs along the west side of the harbour. Three islands, Newcastle, Protection, and Gabriola, along with Duke Point, form the eastern edge. The Port of Nanaimo includes the Inner Harbour, Nanaimo River estuary, Departure Bay, the waters on the east side of Newcastle and Protection Islands, and Northumberland Channel. The port is under the management of the Nanaimo Port Authority.