In reply to Blunderbuss:
As others have mentioned, it's a made path all the way up. You might even get a view if you arrive on top later in the day - might be sunny in the afternoon? You can make a circuit by continuing south over the summit and descending the Three Peaks path. Easy tracks lead back to the Ribblehead Viaduct and the start. Make sure you have a good look at this and show junior just how fantastic Victorian engineering could be. There's a great plaque under it which was put in when they refurbished the viaduct about 30 years ago.