IMO nowadays I feel like East Setauket is hardest trail on the island. It's total mileage is around 22 miles for all 3 parts and has over 2500 ft of climbing. It also contains some of the hardest climbs around. All the newer cuts have really added variety and difficulty to the trail. I really like how sections ride very differenty. To ride East Setauket well, you need a mix of endurance, tempo control, bike control and good braking. It offers some of the few double black diamonds on the island. Except for Rocky Point and Shoreham only trails that have equal length or more. Although Shoreham isn't a clean loop exactly, more of a jumble of trails...With a nice mix of fast downhills, technical switchbacks, and some rocky and rooty sections it keeps you focused and entertained. Definitely a great workout too!!