Great Zimbabwe is a ruined city in the southeastern hills of Zimbabwe near Lake Mutirikwe and the town of Masvingo, close to the Chimanimani Mountains and the Chipinge District. It was the capital of the Kingdom of Zimbabwe during the country's Late Iron Age. Construction on the monument by ancestors of the Shona people began in the 11th century and continued until the 14th century,[1][2] spanning an area of 722 hectares (1,780 acres) which, at its peak, could have housed up to 18,000 people. It is recognised as a World Heritage Site by UNESCO.
Great Zimbabwe served as a royal palace for the Zimbabwean monarch and would have been used as the seat of political power. One of its most prominent features were the walls, some of which were over five metres high and which were constructed without mortar. Eventually the city was abandoned and fell into ruin.
http://en.wikipedia.org/wiki/Great_Zimbabwe