Lyrics: [Donovan Leitch]
Music: Donovan Leitch
Well known as an extended jam played by the Allman Brothers Band, based on a theme from Donovan's "First There Is A Mountain." But the idea of using this theme seems to have originated with the Grateful Dead, who started using it in the late 60's - see, for example, the passage at about 9:00 into the version of "Alligator" on "Anthem Of The Sun."
Fredrik Tydal pointed me to this passage from Scott Freeman's Allman Brothers biography "Midnight Riders":
"'Mountain Jam' was also recorded at the Fillmore. Taking up two entire album sides, it is the Allman Brothers Band at its most ambitious. The jam, tracking in at over thirty-three minutes, grew out of a short and simple folk song by Donovan called 'First There Is A Mountain'. Duane had first played it sitting in one night with the Grateful Dead at the Fillmore East in early 1970 [11 Feb 1970]. The Brothers had opened for the Dead and everyone was flying on LSD. Fleetwood Mac showed up that night and Mick Fleetwood sat in on drums while Duane and Peter Green and Jerry Garcia jammed on 'Dark Star' and then the Donovan song. The Allman Brothers soon added the 'Mountain Jam' to its song list and, in a year's time it had gone from a meandering seemingly directionless jam into a focused and often majestic song that was divided up inyo several separate and distinct movements."More recently, 'Mountain Jam' has been played by Phil Lesh & Friends.