Russo’s Pizza on Diamond Street in Glen Park opens at 11 a.m. Six days a week. By 5:30 a.m. Antonio Russo, 81, is at the dough mixer in the back. He has mixed the day’s dough by hand since 1971. He has not missed a Tuesday in eight years.

The recipe is on a postcard from Capri, sent to Antonio by his uncle Salvatore in 1968. Salvatore wrote it on the back in pencil. The postcard is in a wooden frame above the oven. The exact proportions of flour to water to yeast to salt are visible if you know how to read his uncle’s handwriting and the smudge from a coffee ring covering one of the digits in 1972.

Antonio came to San Francisco from a town outside Naples in 1969. He worked at three other Italian restaurants in San Francisco, one in the Marina, one on Columbus, one in North Beach that closed in 1981, before opening his own place in 1971. He paid his uncle $200 for the recipe and three bottles of grappa from a store on Stockton.

The dough is a four-day process. Long ferment. The flour is a 00 from a mill in Naples that he has shipped in twice a year since 1989. The water is from the city tap, untreated; he says San Francisco water is one of the things that makes the recipe work here. The yeast is sourdough starter he keeps in a clay pot. He named the starter Sofia after his mother. Sofia is 57 years old.

A large pie at Russo’s costs $19 in 2026. It cost $4 in 1989. Antonio has raised the price twice in the last twenty years. He has been offered, by his own count, $1.8 million for the building four times. He has refused each time. The building is in a family trust that goes to his three nieces in Italy and one nephew in San Jose.

“My uncle gave me a postcard,” he says. “I cannot sell the postcard. I cannot sell the dough. The pizza is the postcard reading itself out loud.”

The neighborhood has changed. When Russo’s opened, Glen Park had two delis, three bars, one Italian and one Greek, and a corner store. Now it has yoga studios, a tea shop, two cafes that close at 4 p.m., and a building that used to be the Bank of America branch and is now a sushi place. The pizza shop is the oldest restaurant left on its block.

Antonio’s nephew Marco, 41, lives in San Jose and comes up three days a week to handle the front. He is the heir apparent. He has been making the dough alongside Antonio, side by side, for ten years. He still gets it wrong about one batch in twenty. Antonio, who can tell from across the room, has yet to comment on a wrong batch except by pointing.

On the Tuesday I visited at 5:51 a.m., Antonio was kneading. His hands move in a way that does not look like work. The dough doubled by 9:30. The first pie hit the oven at 11:14. A man named Brian, an architect who has lived three blocks away since 1996, ordered the same pie he has been ordering every Friday for twenty-six years. Antonio asked him how Brian’s daughter’s wedding had been. Brian said it was beautiful. Antonio said: good. He turned back to the oven.