If you want to escape the crowds in Acadia, head to the trails on the eastern side of the island. Acadia Mountain is one of the best of the bunch, as you'll have excellent views over the Somes Sound from its 681ft peak. It's a moderate 1-mile (one way) hike to the top from the trailhead off Highway 102.
If you want to keep going, continue down the eastern slope of the mountain (rather than turning back) and loop back along the Man O'War Brook Fire Rd. Or keep going and you'll eventually link up to the trail up St Sauveur Mountain, which then continues back to your starting point along the St Sauveur trail. This entire loop is about four miles.