His silky visage has watched over New Yorkers for more than a quarter-century, an ageless face observing triumphs and sins, silently offering the promise of a better life, or, at minimum, above-average dermatologic care.

Dr. Jonathan Zizmor, he of the famed subway skin-care advertisements, is the kind of celebrity who can make New York City feel like a small town. To know Dr. Zizmor is to know the city’s secret handshake, to appreciate its quirkier, more pedestrian pleasures that natives claim as their own.

But like other fixtures of an older, rapidly vanishing New York, Dr. Zizmor is disappearing, too.

It emerged on Monday that the doctor, who turns 71 this week, has retired. His dermatology practice on the East Side of Manhattan is now closed. His $3.1 million home in the Bronx — yes, all those pimple removals add up — has gone into contract.

His wife, Alexandra Zizmor, would not say if Dr. Zizmor plans to remain in New York City at all. “No comment,” she said when asked if a move to warmer climes was in the works.