From Maine Turnpike:

Take Exit 2 in Wells, ME.  Turn Right onto Route 109 heading North, keep traveling straight for approximately 16 miles.  At the foot of Mousam Lake, bear left, continuing on Route 109.  The fair grounds is approximately 1 mile on the right.

From Rochester, NH:

Follow Route 202 heading East, to Route 109 (Main Street) in Sanford.  Take a left onto Route 109.  At the foot of Mousam Lake, bear left, continuing on Route 109.  The fair grounds is approximately 1 mile on the right.