Three Forks’s grand Sacajawea Hotel  (Main St. and Ash St., 406/285-6515 or 888/722-2529, www.sacajaweahotel.com , $95–115, lower rates off-season) has been a local landmark since 1910, and in recent years has been through a succession of owners, with several extended closures. When we visited in the spring of 2008, it was open and offering the nicest digs in town, but it was once again on the market. From the rocking chairs on the wide front porch to the big claw-foot bathtubs in some of the rooms, the Sac has an easygoing yet refined comfort.
Just off the I-90 exit west of downtown, Fort Three Forks Motel (Highway 287 near I-90 exit 274, 406/285-3233 or 800/477-5690, http://fort3forks.com , $77 and up) has nice motel rooms and a small RV campground. Pets are accepted at both places for a small fee.
Bud Lilly’s Anglers Retreat (16 W. Birch, 406/285-6690 or 406/284-9943, $65 and up) offers sleeping rooms (shared bath) and furnished apartments in a restored railroad workers hotel. As the name suggests, Lilly (a well-known fishing guide and conservationist) rents most of his lodgings to anglers who are spending a bit of time in the area.