What's the oldest restaurant in San Francisco? That depends on how you define your terms. Tadich Grill has been in business since 1949, but it moved a couple of times, and has been in its current location only since 1967. The Old Clam House has been the same location since 1858.
If the Old Clam is SF's oldest restaurant, then 615 Sacramento is arguably the second-oldest. It opened as Jack's in 1864, was rebuilt in the same location after the 1906 fire, was closed for almost two years in the 1990s for restoration, and closed again in December 2000 when the new owner decided to cash in on the dot-com era real-estate boom and put the building up for sale, asking $4.75 million. At the time, everyone expected it to be converted to offices. However, thanks to the doc-com crash, it languished on the market for most of 2001, and was eventually purchased for $2.9 million by Philippe Jeanty, who reopened it in early 2002 as Jeanty at Jack's.
History aside, the beautifully restored interior makes this one of
the most gorgeous restaurants in the city. The cheapest way to enjoy
the vintage atmosphere is to drop by the bar at happy hour, weeknights
from 4 to 7. Drink options are draft beer for $3 (the pint of 21st
Amendment Brew Free! or Die IPA I had was excellent, and they also had
Chimay), or glass of good white, rose, or red for $7.
The real draw here
Hog Island Sweetwater oysters for $1 each, served with lemon, mignonette, and by request horseradish sauce (to my taste unnecessary with such good oysters). The bartender
said the owner lives near Hog Island and picks them up daily on his way
in. The regular menu also has some dishes that make good bar snacks, such pigs' feet and rabbit pate, at reasonable prices.