The State manages the Castle trails in Moultonboro. They just reported that they groomed their trails and marked them open! You'll have to park in the Castle parking lot on Route 171. This is the only snowmobiling in Moultonboro. Here's what the NH Bureau of trails reported on Friday, 3/17....
4” base; 12” to 30” new snow. Moderate to good riding conditions. Trails were groomed Friday, no additional grooming will be done over the weekend. Use CAUTION – wind drifts, bare spots, icy base. Corridor 26 CLOSED from parking lot; trees down on Corridor 15 south of parking lot.
Web site is at
http://www.nhstateparks.org/