The RMC operates four backcountry facilities in the northern Presidentials; the Log Cabin, Crag Camp, Gray Knob, and The Perch. There is currently a $7/night fee at the Log Cabin, and it operates on a first-come/first-served basis. The RMC Caretaker will often stop by to pick up the fee and check on the shelter. If the Caretaker doesn't visit, you can mail your payment to the RMC in envelopes provided.
The Log Cabin isn't really a full cabin, more like an enclosed shelter. The original was built in 1890 by W. G. Nowell just off Lowe's Path, near the junction with the Randolph Path. There is no stove or cooking area, and open fires are not allowed. It sleeps 10 people, and there are no matresses so you should bring your own sleeping pad. There is no camping within .25 miles of the shelter.