"New Speedway Boogie" is one of the few songs by the Dead literally written about something in particular, Altamont.
In the Maysles Bros'
Gimme Shelter movie, you see the Dead arrive at the Speedway, then they get work of the security shenanigans and hear about Marty Balin getting clocked in the face, and they do an about face. Smart career move.
another BOS to Steve Miller