We plan to hike a 14.5 mile loop (around 3200 ft of ascent) on Mt. Greylock using the Hopper, Money Brook, Mt. Prospect, Appalachian, Jones Nose, and CC Dynamite Trails and Sperry Road. We are hoping for spring flowers and multiple views from the only 3000 ft high ridge in MA.
The leader is planning a moderate and steady pace, but you should be in good shape for hiking for a hike of this length.