Dating back to at least 1882 when the Baganda Kabaka (or king) Muteesa I (1835-1884) established his palace at Kasubi on a site also used by his father.
He was the first Kabaka to be significantly influenced by foreign cultures, and broke with many of the traditions of his forefathers.
When he died in 1884 he decreed that his jawbone should not be removed from his body, and that he was to be buried at his palace in Kasubi. He was thus the Kabaka to be buried whole and at his former palace.
As a result Kasubi became the official resting place of all Kabakas and it now holds the graves of Muteesa's three successors: Basamula Mwanga II (1867-1903), Daudi Chwa II (1896-1939) and Fredrick Walugembe Muteesa II (1924-1969).
Probably the easiest way to get to the tombs is by a 'Special Hire', what we in the west would call a taxi (make sure you negotiate a price before setting off, however). What the Ugandans call a "taxi" is a hopelessly overloaded mini-bus plying a fixed route.