The first such work was St George's Tower, built of coral rag stone in 1074, at the base and tapering significantly toward the top for stability.
12.
The Zanzibar red colobus live in a wide variety of drier areas of coastal thickets and coral rag scrub, as well as mangrove swamps and agricultural areas.
13.
The island has a high coral rag forest with tall trees like " Adansonia digitata " baobabs, which has, in recent years, started to be subjected to extensive clearing.
14.
The species can live in quite dry scrub near the sea or among coral outcrops; in Zanzibar, they are restricted to tall thicket forest growing on waterless coral rag.
