You are thinking about Webster which is right by Rostraver airport. They did close that entrance by the hot dog shop (red caboose), there is about 5 other entrances to Webster, one being my good friends back yard. Webster hill is cut down to about a 1/3 of what it was. Its still fun to ride, but not worth a drive to go there.
We are talking about Creekfalls which is about 15 min down rt. 51 past Webster.