Yeah, you would take Lincoln Gap Rd from route 100 in Warren and go west over the Lincoln Gap. At the end (rt116) you'd go right then right again on rt17 to go back over Ap Gap which would take you back to 100. If you want longer routes or less steep routes, you could do the Middlebury gap (125) or Brandon (73). They all basically go over the western spine of the greens between rt100 and 116/7.
The climbs are detailed well here
http://www.northeastcycling.com/six-gaps/ BTW - I have a camp on Lake Dunmore that the other poster mentioned. I would go to Waterbury reservoir for OW swimming. Closer and better access for OW swims, also no boat traffic.