Seychelles' 115 islands fall under two distinct groups. The tall granite, Inner Islands cluster mainly within the relatively shallow Seychelles' plateau, 4° south of the equator and roughly 1800 km. distant from the east coast of Africa while the low-lying coralline cays, atolls and reef islands of the Outer Islands lie mainly beyond the plateau up to 10° south of the equator. These Outer Islands are divided into five groups: the Amirantes group lying 230km distant from Mahé, the Southern Coral Group, Alphonse Group, Farquhar Group and finally the Aldabra Group, some 1150km from Mahé.