Don’t expect to find fancy accommodations in Deer Lodge [1].
Scharf’s Motor Inn, near the old prison (819 Main St., 406/846-2810, $63 and up) has a restaurant, a guest laundry, and allows pets.
The Western Big Sky Inn (210 Main St., 406/846-2590, $66 and up) has a pool and is convenient to the Grant-Kohrs Ranch National Historic Site [2].
The Deer Lodge Inn (1150 Main St., 406/846-2370 or 877/424-6423, $75 and up) offers a pool and lies right off I-90.
Camp in town along the Clark Fork River at the KOA (330 Park St., 406/846-1629).
Links:
[1] http://www.moon.com/destinations/montana/butte-helena-and-southwestern-montana/the-upper-clark-fork-river-valley/deer-lodge
[2] http://www.moon.com/destinations/montana/butte-helena-and-southwestern-montana/the-upper-clark-fork-river-valley/deer-lodge/grant-kohrs-ranc