Ras Mkumbuu is a long narrow peninsula on the central west coast of Pemba Island, one of the two main islands of Tanzania's Zanzibar Archipelago. The town of Chake-Chake, one of the island's main population centres, is located immediately to the south of it on Chake-Chake Bay. The peninsula stretches due west for 12 kilometres, tapering to only a few tens of metres wide at its narrowest point. The peninsula, along with Fundo Island to the north, forms part of a natural breakwater which provides a calm harbour for the northern town of Wete.