In deference to his wife, Sarah, John Marble persuaded the ATIS Board to introduce some slower-paced, adults only hikes into the 1984 summer schedule. The ATIS Adult Program began modestly in with three trips run exclusively for adults during that summer and has bourgeoned into a program that offers excursions most days of the week during July and August. Volunteers are recruited to lead expeditions to one of their favorite destinations and given guidelines for the trip, while interested adults are asked to contact the leader to get instructions on where to meet and what to bring. Past trips have included everything from dinner on the shores of a beautiful lake to the ascent of a 46er, with short hikes to waterfalls or easy paddles downstream in between.

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