Why not Muir Woods while the weather is fantastic?!
We'll meet at Starbucks at 10 - 10:15 a.m. in Marin City, get onboard a shuttle (as parking is scarce at the park) and reach the park at 11:10 a.m. or meet the group at the park entrance then. Shuttle runs at 10:30, next one is at noon so you might not want to miss the shuttle or you'll have to find parking at the park.
Bring a lunch or dine at the cafe onsite.
We'll do an hour, an 1 1/2 loop or both or just enjoy the ambience of the park then head back on the shuttle at 3:20 to reach the parking lot at 4 p.m.
The shuttle ends at the end of October so it's the last chance to ride it. Cost is $3 roundtrip unless you're over 65, then it's $1.
The park pass is $7. I just got the senior pass for $10 and it's good for life. You can get this at age 62.
If you want to carpool with me from the east bay, just call me.