All that matters is, are you going to be safe? Do you have an idea of your own tolerance? Will you cheer on other people, and keep an eye out for them?” says Maura Twomey of Boston, who grew up in a suburb of Dublin, Ireland, where she taught herself to swim. “People don’t care if you’re rich or poor or what you do for a living. It favors the hardy, the persistent, the well-insulated. Unlike many athletic endeavors, open water swimming is a pastime embraced by many in their 50s and up, way up.

“Some people think it’s just too cold to swim, but it’s not cold at all once you’re in the water.” And then there’s the camaraderie of it,” she says. “It’s so beautiful when you’re swimming in the lake. Her passion for open water swimming is about much more than physical exercise.

“Like most people my age, I have various aches and pains that one just lives with at my point of life. “It makes my body feel so good!” she exclaims. “A lot of us look longingly at the water all year long, but it’s still a little cold for me now,” says Dorothy Harza, 93, of Evanston, Illinois, who swims nearly daily in Lake Michigan from May to November.

And they are the last to, very reluctantly, call it a season in late fall. They are the first to plunge in when those on the shore are still shivering in sweaters. They’ll gush about the color of the water, the angle of the sun, the shape of the clouds. You might not have noticed them, but these quiet few are the ones who seem most keen on noting the shifting tides, the current, the wind. Many beaches won’t open for weeks, but already one dedicated group is quietly pacing the shore.

Ten little fish by audrey wood