I have just seen a postcard of Bolton Castle and remembered visiting it in 1985. It was fairly derelict and totally deserted, we parked the car on the track outside and wondered around for an hour, having now looked at the website it looks like they have furniture in there and hold weddings and other functions.
I remember the days that we used to park the car on the grass verge and wander around Stonehenge, the last time I went there we had to park in the car park, go through an underpass and look over the fence (although that was in 1995 and I dont think they charged which I expect they do now)
In the 70's we used to take the dog for a walk in Bedgebury Pinetum in Kent, park in the car park and wander down to the lake, our labrador treated it as one of his private swimming pools. For a while they had a wooden box that you could put a donation in but it didn't last long, it was broken into too often. Now they charge £8 to park the car which you have to pay by card and enter your registration number so that the barrier will let you out. Then you pay to hire a bike or Go Ape or something or other, or wander along the tarmac paths, following the signposts.
Its nice that places are preserved for future generations, but sad that we have lost something to do that.