SUNDAY

Bike Swap, 10 a.m. to 1 p.m. in Portland

The Bicycle Coalition of Maine’s Portland Bike Swap will be held from 10 a.m. to 1 p.m. at the University of Southern Maine’s Sullivan Gym in Portland. Hundreds of bicycles will be for sale, including mountain bikes, road bikes, classic cruisers, kids’ bikes and hybrids. Volunteers will be on hand to help with pricing and bike fitting. Admission is $3, with free admission for USM students as well as children 12 and under. For more information, call 623-4511.

TUESDAY

Maine Woods Destinations, 7 p.m. April 28, Holden

The Appalachian Mountain Club of Maine hosts a presentation about Baxter State Park and the Maine Woods Initiative. There’s a potluck dinner at 6 p.m., followed by the presentation at 7 p.m. Peter Roderick will share stories of winter adventures in the park and the AMC’s 67,000-acre initiative in the Maine woods. The talk is at the Fields Pond Audubon Center. No cost, all welcome.

UPCOMING

Neighborhood Bird Walks, 7 a.m. May 8, Brewer

The Penobscot Valley chapter of Maine Audubon will hold neighborhood bird walks May 8-29. The first walk will be at the Indian Trail and Penobscot County Conservation Association in Brewer. The walks are free and open to the public, but no pets are allowed. Rubber boots or waterproof shoes are recommended. Meet at the Penobscot County Conservation Association on North Main Street in Brewer. To learn more, call 989-2591.

Adventure Race, all day May 9, Danforth

The 20-mile race includes a compass run, mountain biking, paddling, and a mud crawl. The cost is $20. More than $1,000 in prizes will go to youth divisions. Proceeds benefit East Grand High’s outdoor education program. To learn more, go to eastgrandschool.org/adventure-race, or write to [email protected]

Quarry Road Ramble 9 a.m. May 16, Waterville

At the Quarry Road Recreation Area just off North Street, Maine Master Naturalist Susan MacKenzie will lead a walk along the trails and Messalonskee Stream. This ramble is suitable for people of all ages. Donations will be accepted to support the trails. To learn more, call 861-3292 or go to quarryroadrecarea.org.

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