Gannon Therrien, 6, of Presque Isle is one of the three youngest participants in the 20th annual Trek Across Maine - Sunday River to the Sea, sponsored by the American Lung Association of Maine. He and his parents will join approximately 1,600 trekkers on Friday as they leave the Sunday River Ski Resort in Bethel for the first leg of a 180-mile, three-day event to raise money for the association.

The trek is one of the state association's biggest fund-raisers of the year, according to Bob Verrill, ALAM manager of special events, who is in his 15th year of overseeing the event.