The place where boxing's GOAT Muhammad Ali lived -- and actually boxed -- is up for sale ... and it could be all yours for a cool $2.9 mil.
Ali's widow -- Lonnie -- is selling the Berrien Springs, Michigan farm that Ali bought in 1975, about 10 years before his Parkinson's diagnosis ... and it comes with a legit boxing ring in the gym.
The place is massive -- 81 acres -- and it features two houses, a bunch of garages, a steam room, a massage room and a full-length basketball court .