Lots of singletrack run through the park, which is heavily wooded. Lots of big climbs and long downhills, some jumps and obstacles made out of logs, stream crossings, tight switchback curves, and what appear to be either sinkholes or abandoned mine shafts (these are surrounded by orange fencing, but keep an eye out for them). There is one main trail that runs through middle of park and all others branch off of that for the most part. Have fun!
Take Cedar Cross Road (at Olive Garden) South from Highway 20. Turn right on North Cascade Road. FDR Park is a few miles out of town, and the turn-off is an unmarked gravel road at Story Book Hill Childrens Petting Zoo. Follow gravel around zoo until you get to a gate. Park at the gate (don't drive through if it's open). Can be hard to find.
http://www.singletracks.com/item.php?c=1&i=3103