North of Portland near Minot, the Hemonds Motocross Park has a motocross track with a 60+ foot tabletop jump. The track is fairly flat and very fast.
To reach Hemonds Motocross Park from the Maine Turnpike, use Exit #75 (old Exit #12) for Auburn. Turn left onto Route 100 and go 4 miles. Turn left onto Route 121 (at Roys All Steak Hamburgers) and go 5.5 miles. Turn right onto Route 119 and go 3.3 miles to the park on the right.
Overall, Hemonds Motocross Park is the 12th most popular dirt bike trail of all 15 dirt biking rides in Maine.