Deerlodge National Forest is a National Forest, where dispersed camping is usually allowed outside developed sites unless posted otherwise. On Birds Of Passage it has 4 free camp spots, 15 paid or permit campgrounds, 9 cabins or lookouts, 1 more where the fee isn't confirmed.
Fees, seasons and closures change. Check with the managing agency before you go. Official data: Recreation.gov, USDA Forest Service, National Park Service, Bureau of Land Management, Recreation Sites and Trails BC.
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Birds Of Passage