Bay seniors eager for more evidence of San Francisco’s vivid history might want to venture to the Old Mint this Saturday from 11 to 5. The 2014 SF History Expo features films, lectures, genealogists and representatives from local history societies, plus a treasure hunt sponsored by the Treasure Island Museum. It’s worth the trip just to check out the Greek Revival glory of this original Mint. Built in 1874 it survived the 1906 Quake as did the $300 million in bullion it housed. Renovations are proceeding apace with the hope that one day soon it will permanently house the San Francisco Historical Society. $5. BART accessible.