Mangapwani (meaning \'Arab shore\') lies on the coast, about 20km north of Zanzibar Town. The Coral Cave is a deep natural cavern in the coralline rock with a narrow entrance and a pool of fresh water at its lowest point. Later, the area became the property of a wealthy Arab landowner called Hamed Salim el Hathy who had many slaves working on his plantations. During this time, the cavern was rediscovered by a young boy searching for a lost goat. Local people were able to use the water again, and Hamed Salim arranged for his slaves to collect the water regularly for his own use. It has been suggested by historians that the cave may have been used as a hiding place for slaves after the trade was officially abolished in 1873. his large natural cavern with a freshwater pool was originally used as a source of drinking water for local people and is rumoured to have been used in connection with the slave trade.