I believe the medieval-style castle is still standing. The other attractions possibly were worn down given you mentioned the 80's. Also there is more space for the trails and an overlook of the city where if you're lucky you can catch the sunrise and or sunset - the seating area you mentioned sounds nice. Now there are benches. I can say the mentioning of a basement not being there anymore is a good considering the crime rate.
I lived in High Country IV since 85 before Fox Run elementary was built. At the time the park was still private property. Every day people drove their cars straight up trails that are now modified or overgrown as a city park. I know that the base for a 3 story tower is still near the overlook a square that is near the overlook water fountain. That tower had a steel rung ladder built in the exterior wall. I definitely heard of stories of injuries falling from the tower. I believe that tower was bulldozed around 87? I remember the basement perimeter as well. That can also still be found but has been filled in. Satanic rituals were definitely happening in the late 80s. We had a pentagram drawn in blood on our front door. Another time driving home on Nacogdoches a gigantic hundreds of feet across 🔥 pentagram was lit as we drove by. It was surreal and ridiculous. People could be weird as hell up there back then.
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