Hazel Loop features 15 miles of hiking trails near Folsom, CA.
I usually park in old folsom in the parking lot next to the old train turnstile. ride northeast down to the river and cross the bike bridge, turn left and go under the bridge and right after that the singletrack will start off to the right. from there on just follow the bike tracks wherever you think you're lost. there are a few different ways to go so just try them all out. you'll get to where you have no choice but to go back on the paved path, go around and cross hazel bridge, stay right on the bike path and you'll end up in the park parking lot, go through it and on the other side there is more singletrack. on this side of the lake you'll have to look a little harder for the singletrack, but it's there.
http://www.tripleblaze.com/trail.php?c=3&i=940