FYI, the walk from Powell BART station to MMC is all uphill, and through a tourist-heavy area. If you are carrying luggage, you may want to walk to a nearby street corner and get a cab/Lyft/Uber to pick you up.
A pleasant walj through tourist-laden area, with a suitcase it becomes a longer walk.
I took uber on a Friday late afternoon from San Mateo. It cost me $36.
Powell street station, about 10 minutes walk.
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