About a thousand years after the walls of Fort Ancient were built, two small serpent effigies were laid down in the valley on the other side of the river, where today Camp Kern is located off State Route 350. The original limestone serpents remain safe underground, but it’s possible to see reconstructions built above them. Site archaeologist Jack Blosser explains how they were used:

Kern Effigy One marks the summer solstice sunrise and is forty-nine feet long. The last ten feet is curved with very large pieces of limestone. From the time the sun rises, the shadow of (a pole at the serpent’s head) will go all the way down the length and the curvature of that snake in a thirty-two minute period. Kern Effigy Two, marking the winter solstice, is one hundred and fifty feet in length.

The hilltop enclosure plays a part in the drama of the summer solstice event, since the sun’s early rays reach this point through a huge ravine in the west side of the North Fort. Camp Kern also runs the Ozone Zip Line, including a crossing of the river gorge at two-hundred feet above the water, and landing just below the rim of Fort Ancient.