I am taking my mom on a little trip to Northern Cali this August, (I am late 20's and she is mid 50's). We are flying in and out of SFO. I am trying to decide how many days to spend in SFO and how many to spend in Mendocino. How many days is sufficient? I hear there are botanical gardens, spas, and horsebackriding. Any help would be greatly appreciated. I am about to purchase all my lodging and would like to make good decisions.