It's a magical place. It was a place where you could be a king, queen, or princess. It was a fortress to be protected by medieval knights from unwanted attackers. It held a dungeon that you could be banished to (although I never went down there...I was too afraid of snakes!).
Although it's overgrown now, there are some signs that young people continue to use it.
There's a worn path and broken glass indicating that some young people may have been partaking in things they shouldn't be.
I guess in that no matter how some things change, there are always some things that stay the same.