The sign in the background of the first pic says "Bill-Fran."
This indicates that it is the Treehouse Fun Ranch in Devore, CA, about 50 miles east of Los Angeles. It was owned for a time by Bill and Fran Flesher (really).
http://www.nudistclubhouse.com/group...php?topic=2574
The style of the girls' hair seems to say mid-1970s. This and shoes are the best way to date the pics. I once took pictures at a Miss Nude USA contest there. About 15 years later, I showed them to a female friend who correctly identified the year as 1979 simply by looking at their shoes. Shoes? Who even knew they were wearing shoes?!