Near Westerly, the 10,000 acre Arcadia Management Area has a great 30 mile mountain biking loop formed in part by the 13 mile Breakheart Trail. It is a gently rolling singletrack with rocky stream crossings and short descents through magnificent pine, oak and beech forests.
To reach the mountain biking trailhead from SR5, use exit 5A onto SR102 south. Turn right on SR3 and follow signs for SR165. Turn right on SR165 for 2.5 miles and park just past little white church.
Overall, Arcadia Wildlife Management Area is the 1st most popular mountain bike trail of all 3 mountain biking rides in Rhode Island.