They cost more than dorm bed space but are still usually cheaper than hotels.
The Sun
Take a comfy dorm bed (22.50) for super cheapness, or grab some friends or family and book a private room for five (90 per room).
The Sun
Camping starts from 15 per person, per night and dorm beds from 21 per night.
The Sun
They're sold by most affiliated hostels along the route and grant access to heavily subsidised dorm beds costing as little as 2 a night.
Times, Sunday Times
Dorm beds are from 14 but doubles starting at 58 or superior doubles would be my pick.
Times, Sunday Times