The best trails are labeled #5. There is the main trails which are mostly singletrack with some wooden bridge crossings, some short climbs and descents. Off of the main trails are some newly made single track which is very tight, technical, and challenging. These are off of the #5 trails and you must look to your sides to find them. One set is loaded with some ravines which decend and then go back up quite abruptly. Also trails labeled #2 are good trails to ride. Stop at the ranger station just after the main entrance to get a map.
How to get there:
Turn off of I-39 on Lake Bloomington Road and turn to go to Evergreen Lake/Comlara Park. Follow this road till you see the main entrance for the Park and go in there to get the map. For trails #5 get back on the road you turned off of and follow it around past the dam. I like to park at the big gravel area just before the woods end. From there you can go either direction on the trails and you won't be too far from your car if you have an unfixable breakdown on the trail. As stated before the main trails are easy to follow, but the real fun singletracks are found off to the sides. If you know someone familiar with the trails, it would be best to go with them the first time.