Aira Force is maintained by The National Trust and is, in a word: Beautiful. I visited with my boyfriend back in September after a recommendation from the owner of the guesthouse we had stayed at in Penrith.
The drive to Aira Force through Ullswater was lovely and when we arrived there was a large car park with plenty of available spaces and a tea room (which I didn't actually see, but did see a sign for) Parking was not particularly cheap unless you are a member of The National Trust and then it is free!
There are a couple of different walks that can be done on the map, but we just decided to choose a path and follow it. The paths are well maintained but in some places it did get rather steep and involved steps, so might not be suitable for everybody. The walk offered lots of lovely places to stop and take photos of the water, trees and general beauty that was on offer. There were also some unusual trees along the way, including the trees that had been filled with hundreds of coins!
We walked up one side of the waterfall, then crossed over the other side and walked back in a loop. (We could have carried on at this point, but we had only paid for a couple of hours on the car park) We crossed over a couple of lovely bridges and certainly enjoyed looking up at the 65ft waterfall drop near the end of the walk.
Aira Force is one of the best walks I have ever been on and I would recommend this to all. Walking boots and a bottle of water are definitely a bonus too!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.