You never know what you might find on a Chicago rooftop—a classy lounge, a chill patio, a collection of lawn chairs. But from the Loop to the neighborhoods, there are a few rooftops that are home to a different kind of buzz—the literal buzz of hundreds of thousands of honeybees.

Beekeeping is nothing new in Chicago. There were 124 beekeepers with 340 colonies in Chicago registered with the state as of November 2014, according to the state Department of Agriculture (keepers are supposed to register their hives or may face penalties).

Their hives are on rooftops and in community gardens. Their wares are at farmers markets, online, in shops or just shared. The keepers are old, young, and living in all different neighborhoods. But after talking to several, it’s clear they share one thing: They’re pretty crazy about what they do. Here are their stories.

Jefferson Shuck and Michael S. Thompson, Chicago Honey Co-Op

Jefferson Shuck, 24, of Logan Square, got into beekeeping by what he called a series of “happy accidents.” After he moved to Chicago around Christmas 2013, he searched for a local honey company—he has allergy problems, and honey is a good form of allergy relief, he explained, because ingesting pollen from the plants that cause problems can help alleviate them. That search led him to the Chicago Honey Co-Op, where he met Michael S. Thompson, 64, one of the founders of the group. The two men talked about both growing up in Missouri, and when Shuck called the co-Op two months later, asking if they needed help, Thompson remembered his Missouri accent. Shuck started working with them last year.

The co-op has about 30 members and four sites in Chicago, for a total of about 50 hives, each of which can have about 50,000 bees in the summer.

On a recent Monday morning, the two of them worked to collect frames of honeycombs from hives atop Christy Webber Landscapes, a building not far from a Metra yard. With the city skyline visible behind them, they worked carefully to brush the bees off each frame—Shuck using a brush, Thompson using a bundle of branches he cut from a rooftop plant—before placing the frame into a box, which they would later cart away by bicycle to their warehouse for harvesting.

Shuck, who also works as a massage therapist, said he finds beekeeping therapeutic. You have to move deliberately and slowly, like a meditation, he said, and use all of your senses: sight, taste (in tasting the honey), touch (in having an awareness of where your body is, so you don’t bump into the hive), smell (he said he thinks a young, healthy hive smells like the head of a newborn) and sound (a hive with a laying queen, he said, will buzz like a revving car engine when doused with smoke).

He doesn’t keep his own bees, though he has been thinking about it for next year.

Thompson became a beekeeper when he was 12 years old and living on the edge of Wichita, Kansas. He had hounded his parents for a beehive, and they finally bought him one for his birthday.

When he moved to Chicago at 19, he found that he missed beekeeping and growing food, but he soon realized that he had everything he needed in the city: the perfect climate, rain, good soil. He teaches about 60 students a year in beekeeping classes in the winter and spring. The Co-Op is his full-time job, but he had been a landscape contractor for 25 years.

Thompson said beekeeping is “very hard, heavy, hot work,” but also incredibly fun. “There is just this magical thing about having honeybees, and even though I’ve been keeping them all my life, every time I open a hive, this mystery occurs,” he said. “There is such a beauty to it that words can hardly describe it.”