From the hilltop Ski Area parking lot, ride north on the Gasline trail (straight, flat, wide-open trail) until you reach the top of a steep downhill - look to your left and you'll see the south end of the Brown Bear trail heading off into the woods.
This is a short, rooty trail that's good for a technical challenge - particularly in the summer. In the winter, snow smooths out the obstacles and makes it less difficult - even a little bit of snow helps. Lots of nice rootballs, some of which are conveniently in the middle of steep uphills. Try to ride it in both directions without dabbing a foot!
I like to make a loop with this trail and the south segment of Black Bear