I think Santa Rosa is relatively new 
ie late 80’s / early 90’s. Built around the same time as Petaluma park and some other northern Bay Area parks, and they’re all pretty similar in design. Love me a lump n bump park.
I was last going to suggest Stone Edge in Florida as being a proper old relic but now I think about it, it was probably built towards the end of the 80’s rather than the 1970’s era. As @anonymity mentioned, most of those were ‘dozed way back.
