The Kilombero Game Controlled Area is located within Kilombero Valley. The area has a coverage of 140km long and 40km wide, west of Selous Game Reserve, the nearest town is Ifakara
The area is consisting of a seasonal flood plain, Miombo woodland and fragments of eastern-arc ever-green forest, so rich in biodiversity. The large part of the area is dominated by the Kibasila Swamp, and Kilombero River, which forms part of Africa's largest river basin joining the Great Ruaha, Rufiji and Luwegu rivers.
The Area is famous for the greatest population of buffalo in Africa and has been on the hunters' spot for it's big manned Lions. Other large mammals include elephant, zebra, endemic species of Crocodile called Crocodylus niloticus and endemic population of Colobus Monkeys. It has maintained populations of a variety of large mammals and is estimated to hold up to 76% of the world's remaining puku antelope (which are only found in 18 location in Africa), Kobus vardoni Livingstone.
For bird watchers, Kilombero GCA contains a remarkable number of bird species and plant ecology. Kibasila Swamp, is famous for wet birds and Magombero Forest Reserve for forest birds. Species that inhabit and are endemic to the area include Rufous winged sunbird, Kilombero weaver, Melodious cisticola, Kilombero cisticola, Iringa akalat, Dappled throated mountain robin and Udzungwa forest partridge.
Kilombero valley is a unique and complex area; it is amongst the largest seasonal wetland in East Africa. The Valley is the main factor for Selous - Kilombero wildlife Migration, in which the population of crocodile and hippo in Kilombero links with that of Selous Game Reserve