I believe CHAOS (Cal Hiking And Outdoor Society, formerly the UC Berkeley Hiking Club) is still CHAOS’ing out of Berkeley. Although primarily under-grad and grad students, since the 1980s, has also had university hangers-on: age-adjacent young adults who know to look to college campuses for social and activity groups.
Look for a sign board on the bridge over Strawberry Creek just north of Sather Gate. Used to be that they’d meet somewhere (pizza or burrito place) on Wednesday nights to discuss day hikes and day trips to rock climb (Point Reyes to Mount Diablo to Pinnacles) and 2-3 night backpacking trips (often in the central Sierra but sometimes Lost Coast or Lassen or further afield) each weekend. And week-long trips, although often by invitation only, over Spring Break.
Annually, there’s a “Dart Trip” for which you come already packed for anywhere and a blindfolded hiker throws a dart at a map of California and then you try to get as close as possible to that location.
Twice a year, there’s a “Gourmet Trip” which has three rules: gourmet food, or formal or semi-formal dress and a stupid toy that you’d never normally bring backpacking 6 miles in (basketball backboard, skis to ski beach sand dunes, a 8-inch reflecting telescope (he went on to kill Pluto), or a hot tub (several people helped me carry it in). I met my wife on the 1992 Gourmet Trip to a Point Reyes beach (Pacific side) and got married 6 years later on a beach on the Tamales Bay side.
Late last century, the Sierra Club had organized trips planned months in advance for members. Mild to moderate, families are welcome, but my impression was it tended towards middle- and very middle-aged folks.
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