The beach is about 10 kilometres (6 mi) long, from the Kongo river to the north and Galu beach to the south (the southern point of reference is an old Baobab tree). It is adjacent to the town of Ukunda, the population of which nears 100,000 inhabitants. A small airstrip is located between the beach area and the Mombasa-Lunga Lunga road. The water remains shallow near shore, with some underwater sandbars near the surface which allow wading with a clear view of the sandy bottom. Inland from the beach, there is extensive vegetation (see photo at right), including numerous palm trees which cover the coastal areas, unlike the dry acacia trees of the mountainous Kenyan Highlands. The Mwachema River flows into the sea at Diani Beach. 
The general area is known for its coral reefs, black-and-white colobus monkeys, and for the closely locatedShimba Hills National Reserve, a wildlife reserve which looks out over the Indian Ocean. Diani Beach has high-class restaurants, hotels, supermarkets, and several shopping centres.