Brass disk marking SF’s geographic center is stolen

The marker at the geographic center of San Francisco, before it was stolen. The marker at the geographic center of San Francisco, before it was stolen. Photo: Connor Radnovich, The Chronicle Buy photo Photo: Connor Radnovich, The Chronicle Image 1 of / 8 Caption Close Brass disk marking SF’s geographic center is stolen 1 / 8 Back to Gallery

The great city of San Francisco no longer has a center.

A brass surveyor’s disk, recently installed on an Upper Market-area sidewalk to mark the precise geographic center of San Francisco, has been stolen.

On Wednesday, city surveyors and Public Works Director Mohammed Nuru visited the spot in the 700 block of Corbett Avenue to call attention to the disk and to the work of the surveyors who had established the spot as the precise center of town.

It wasn’t technically the center of town — that spot is under a bush on a nearby hillside — but it was close, and it was publicly accessible.

At the time, surveyor Michael McGee predicted that the small brass disk — attached to the concrete with heavy-duty glue — would suffer the fate of similar markers and be stolen by vandals.

“I’d give it about six weeks,” McGee said.

He was off by five weeks and six days.

On Thursday, an orange arrow and shakily written “Geographic Center of City” were still on the sidewalk. A circular patch marked the spot where the disk had been, briefly.

“We’ll replace it, and we’ll secure it even better,” said Public Works spokeswoman Rachel Gordon.

Steve Rubenstein is a San Francisco Chronicle staff writer. Email: srubenstein@sfchronicle.com