Downtown merced there's a museum.panic tables too.
They do have a section right off the parking lot. It has I think three or four tables. They're round with 4 chairs each so probably not enough for 20 people. As for the rest of the facility I don't recall. I'm not from that area either, so I can't comment further. I just recommend calling the museum and asking them. They are pretty familiar with the area around and may be able to help.
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