From UgandaWiki , the Uganda online encyclopedia

Geography
Kampala in located in central Uganda, on the northern shores of Lake Victoria. It is bordered by Wakiso District to the North, East, West and South–West and Lake Victoria to the South East. It is 169 sq.km in size. With an altitude of 1180m above sea level, Kampala has a pleasant weather, with annual temperatures averaging 17 degrees (minimum) and 21 degrees (maximum) Celsius. It has a population of 1.5 million people (Uganda's population is estimated at 29.8 million).

History
The history of Kampala, like that of many other cities in the world, derives from both folklore and historical fact. According to folklore, much of the area where present-day Kampala stands was dominated by wetlands and rolling hills. This made it an ideal habitat for the Impala and other members of the antelope family. They grazed on the slopes of the hills and came down to the wetlands for water.

The palace of the Kabaka (king) of Buganda, located on one of the hills, overlooked this landscape rich in Impala. He turned it into his hunting grounds. Folklore merged with history when the British Empire builders arrived at the end of the 19th century. "Impala" was the English name for that particular antelope family. So the British referred to the area as the "hill of the Impala".

The Baganda, eager to adopt foreign words into the local language, translated "hill of the Impala" into Luganda as "kasozi k'Impala" (pronounced "ka Impala" and eventually "ka mpala"). So whenever the Kabaka left his palace to go to hunt his favourite game, royal courtiers would say "the Kabaka has gone to Kampala to hunt". The name stuck.