CARRABASSETT VALLEY — A recreational trend that emerged from a technique first used by scientists to study the rain forest canopies of South America is catching on at ski resorts around the country, including Maine.

On Aug. 7, Sugarloaf Mountain and Sunday River hope to be zip-lining their guests through the trees slopeside, a resort spokesman said Friday.

Still dialing in the specifications and making some final adjustments to the course, Sugarloaf Competition Center Manager Jim McCormack said the new activity adds to the non-snow-related things people can do on a mountain.

“Kids are going to really like these,” McCormack said with a broad smile as he gave a demonstration ride on three of the resort’s six interconnected lines. He said teens especially would find the zip line thrilling.

McCormack’s summertime duties now include being the zip line manager.

The lines, actually steel cables, are strung between trees 10 to 20 feet in the air. Attached with a rock-climbing harness, locking carabiners and a trolley device that rolls over the cable, riders dangle and “zip” downhill between trees. The length of the runs at Sugarloaf range from about 150 to 200 feet.

For safety, riders must weigh at least 65 pounds but not more than 275 pounds.

The terrain below features everything from craggy ravines to babbling brooks. In the summer, people can see — from a bird’s-eye view — a few of the glades they might visit in the winter, Sugarloaf spokesman Ethan Austin said.

Riders will reach speeds of up to 25 mph and are slowed and stopped by a guide who uses a braking block attached to a tether. Riders are also attached with a second safety line to the zip cable as backup protection to the main rigging.

Platforms attached to the trees allow guides to help guests attach and detach from the cables.

Boyne Resorts, the company that owns Sugarloaf and Sunday River, has similar zip lines at its resorts in Michigan and Montana. Success with those operations prompted the company to bring them to Maine, said Brad Larsen, Sugarloaf’s director of sales and marketing.

“Our sister resorts have had tremendous success running these zip-line tours and we’re excited to be able to offer this new attraction to our guests,” Larsen said in a statement. “It will be a truly unique summertime attraction and a thrilling ride for guests of all ages.”

Resorts across the United States have been adding zip lines to their lineups for several years in a growing trend that seems to have begun with rain forest canopy tours offered to guests of Caribbean cruise ships.

Austin said the resort would run the lines in the winter, as well, “at least until the snow gets too deep.” The resort hopes to illuminate the lines to offer skiing and snowboarding guests another activity to do at night.

The lines are meant as another attraction and not as the main event at the resort, Austin said. It will be another activity for those coming to ski or golf at the resort, or as an alternative for those who don’t want to ski or golf.

Tours on the lines will be conducted with guides assisting guests. A 1½- to 2-hour tour will cost $39 per person.

At Sunday River in Newry the tours will cost $49 for adults and $39 for children under 12, said Darcy Liberty, the communications director for both resorts.

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