Much of the Adirondacks is covered by glacial remnants. Eskers are tall narrow reminders that water flowed beneath the glacier.
Glacial till carried by streams was deposited along stream beds, forcing the water higher and carving out deeper, that is, taller, channels along the underside of the glacier. Often you come across a road through the Adirondacks that travels along an esker for a distance with banks dropping off steeply on both sides.
This particular esker, near the floating bog mat in Stillwater, is eroding more recently by changing levels of this dammed-up lake.