It's only open for part of the year and is invaluable during that time but you do need to book a bed at Rowardennan Hostel ahead of time because the only other non-camping accommodation here is the rather expensive Rowardennan Hotel. It might be of interest to know that the latter runs ferries across the loch three times daily during the main visitor season. The hotel is also a good place to go for inexpensive meals while the hostel will provide a simple continental breakfast for a few pounds above the standard overnight tariff. Other extra cost services like packed lunch provision and towel hire (for the forgetful!) are also on offer.