Assuming you mean Osama Bin Laden, it's often assumed that up until recently his 'lair' was the Tora Bora region of mountains near Kandahar or, more accurately, a series of purpose built caves beneath them. However his presence here has never been proven sufficiently. His last known whereabouts, proven beyond any reasonable doubt, was in Sudan from 1992 to around 1995 (when it is believed he fled back to Afghanistan). It is well known that whilst in Sudan he based himself in Khartoum. However the city is dissected into a series of independent districts and administrative areas based upon ethnic and religious backgrounds. Osama stayed very much within the Syra Syra (pronounced See-ra, See-ra) area of Khartoum, so if anywhere could be described as his last known 'lair' I'd say it was Syra Syra.