When is the best time to visit Sunday River with a large group?

December through February is the busiest time at Keystone Lodge, 3 miles from Sunday River, and the lodge is open all year with a hot tub facing the mountain and a seasonal outdoor pool from Memorial Day weekend through Labor Day.

Winter is the reason this lodge exists. Sunday River has 8 connected peaks and 139 trails, and its season runs from Halloween into early May in a typical year. December, January, and February are the peak months, and peak ski weekends and holiday weeks fill 4 to 6 months out, so a large group should book early. Weekends and ski season carry a 3 night minimum, and Thanksgiving, Christmas, and New Year's carry 4. A 4WD or AWD vehicle is strongly recommended on the mountain roads.

Fall brings the color. Foliage weekends also fill months out, and the deck and great room look straight at the mountainside.

Summer, May through September, is the pool season. The seasonal outdoor pool is open from Memorial Day weekend through Labor Day, weather permitting, and a private pool is rare around Sunday River. Grafton Notch State Park is 18 miles, Screw Auger Falls is 14 miles, 2 golf courses are 6 miles, and Sunday River runs lift served mountain biking and a scenic Chondola ride to the summit. July 4th carries a 4 night minimum.

April into May is mud season, the quietest stretch of the year around Sunday River, which usually means the easiest availability for a group that needs the whole lodge.

Whatever the month, a storm day does not cancel the trip. The game room, the TV lounge, the gas fireplace, and the hot tub are all yours.

Live rates and open dates for Keystone Lodge are on the booking page. Book direct and skip the platform service fees.

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Facts on this page were checked on September 19, 2026. Questions? Email [email protected] or call +1 (307) 284 3818.