Located just north of Lexington, this is a great 12 mile ride that features a good mix of beginner and intermediate terrain.
Park on the grass lot to the left of the road. You'll see a KYMBA sticker on the sign for verification. Bike up the road, go past the gate, and take the second trail entrance on the west side of the road. This is the Green Connector, a rooty and rocky singletrack that will connect you from the main road to the Blue Loop.
Once you reach the Blue Loop, turn right and follow it. It is 4.5 miles of beautiful singletrack that winds around beautiful scenery including Big Sky Pond. Eventually, you'll come to Orange Connector where you'll turn right.
Follow Orange Connector to the Orange Loop and ride it in the clockwise direction. The Orange Loop has an awesome variety of obstacles. There are large log rollovers, planks, bridges, and rocky switchbacks. The obstacles are grouped together with areas known as "Plankton" and "Logville."
Once you've completed the Orange loop, retrace your steps on orange connector and turn right to complete the unridden portion of Blue loop.
The trails are marked very well - KYMBA Bluegrass chapter has done some great work out here.