I’m in Scotland and have no TV in my place so I can’t see it as it is.
Looking at a satellite image of the area on Apple Maps, there are areas that look like they are used by maintenance. I can see piles of sand and the like. They probably put the fence up to keep people out of there and to simplify rulings as it becomes much easier to deal with knowledge or virtual certainty issues if you make the entire area one large TIO.