Circle Trail is a loop trail located near Killington, Vermont. The trail is rated as moderate and primarily used for hiking.
I visited this trail in early Nov 2015. I hiked up to a summit just off of this trail. It is a challenging, uneven/rocky trail, but well worth it. There were several people with dogs and kids, though I think many kids would struggle. The summit has a really cool view of the valley, which is ~250 degree panorama. (n.b. We were advised that some hikers climb over the summit, and require rescue. Having seen it, I can see how this could be tempting, but unfortunate.). This trail gets your heart going, made my quads hurt, and crosses the AT. I would definitely do this one again!