Jackson sucks for cycling. The surrounding suburbs are fantastic...bike paths everywhere. Also, there's the Mule Jail Trail for mountain bikes they just opened. It used to be the Mule Jail Hunting Club but the sprawl from Jackson has caught up with it so it's no longer safe. I don't have a mountain bike, but there's some great woods back there so it's probably pretty nice. For roadies the Natchez Trace is hard to beat...tons of wildlife and zero developement.
