At Doug’s Gym you couldn’t watch TV while walking the treadmill because there were no TVs—or treadmills. There were no ellipticals, no heart-rate monitors, no hot yoga. There was no air-conditioning. There were, however, dumbbells, kettlebells, and barbells—row after row of them—a few bench press set-ups and a leg press, a boxing ring, a heavy bag, and a handful of plug-in fans, most of which worked.

Situated on Commerce Street in Dallas, above the office of a working-man’s lawyer (“Traffic Tickets $45”) and across the street from the downtown police station where Jack Ruby shot Lee Harvey Oswald a year after the gym opened, Doug’s was a place frozen in time. Virtually nothing had changed since its first day in business. Three years ago, when photographer Norm Diamond wandered in and asked if he could take pictures, Doug Eidd, the then 86-year-old owner agreed, but added, “Photographers have come here before. You’re not going to find anything new.”

Of course, Diamond wasn’t looking for anything new. Quite the opposite.

His previous book had focused on the forlorn items he’d found at Dallas estate sales; at Doug’s he was attracted by the gym’s time-capsule quality, and by an old man who had dedicated his life to helping people change themselves. But six months later, in the spring of 2018, as it became clear that the neighborhood itself was changing, the landlord saw an opportunity to sell the building to a developer. After 55 years, Doug’s closed. And when that happened, Diamond found something else: a quiet reminder that regardless of how hard we push and how tight our grip, we must, eventually, let go.

Diamond’s new collection, Doug’s Gym: The Last of Its Kind (Kehrer Verlag, February 18), is a bighearted photo book that walks the line between elegy and celebration. Here are twelve of the book’s most memorable photos and the stories behind them.