The piscataquog dirt jumps are back there. It's not what it used to be, it got bulldozed a couple times but there's still some jumps back there. I wish I had a picture of what it used to look like, it was impressive like 10 years ago. If anyone wants to find them, find the bridge behind Delta stadium, cross the thing and take the second left. It's the trail parallel to the trail following the river that your looking for. About 50 yards down to your right you'll find the jumps.