On a visit to one of the 21 Missions of California, my husband and I spent fair amount of time visiting the grounds. We saw many olive trees planted by the old Spanish friars. They were full of fruits.
The olives were just falling on the ground, I don't think they were used for anything. So (ssshhh!) my husband picked some and pickled/cured them when we got home. Months later we enjoyed them and remembered our visit to Mission Soledad.