Camping
Rishiri Hokuroku-yaei-jo
The campground, which is the northern trailhead for Mt. Rishiri, is about 3km from the ferry terminal. Either walk, or take a taxi. The campground office has limited hours 9-5, and sells soft drinks and beer. If you want a bath, go back towards Oshidomari about 2km to the Rishiri Fuji Onsen Hoyoshisetsu, which also has a laundry machine.
Rishiri Family Camping Ground
This family campground, so you can drive your car to your tentsite, is about 1km from the Oshidomari ferry terminal.
Lodging
Momoiwa-so Youth Hostel
Nothing in the world can quite prepare you for a stay at this wonderfully wacked youth hostel, but if you bring a huge dose of self-irony and enthusiasm, a stay here can easily turn out to be your greatest experience in Japan. While the 9:30 lights out and a strict no alcohol policy, can sound dull, rest assured, after a day of hiking, singing and dancing you won't mind one bit. The hostel is nicely located next to the sea at the end of a dirt road just around the corner from Momo-iwa Peach Rock.
Hostel 3.9
It was open in June 2009 and everything is sparkling new. The owner speaks English well and can give you advice on hikes and restaurants. The owner may also give you a ride to/from the trailhead. No food is available, though tea is.
backcountry
Everywhere on Rebun and Rishiri can be reached by day hikes, so there is no backcountry.