I stayed at Twin Mountain Motor Court & RV Park in Twin Mountain, NH for 5 days in early August 2008. The park is behind the motel on the west side of Highway 3 between I-93 and Highway 302. Their website is:
Some comments about the park: No trees, gravel interior roads & sites. Some grass.
Easy to maneuver. Abundant wildlife visits the park every evening.
Located behind the motor court on west side of US3 approx. 9 miles north of I-93 exit 35.
We paid $28/ with 30 amp full hookup. We camped in a 45 foot motorhome with tow car.
Park is convenient to Franconia & Crawford Notch State Parks and all White Mountains sites and attractions.