It is conceivable that the dike will only get deeper, judging by the large volume of water that, although hard to see here, was flowing through it at the time thisphoto was taken. The rest of the Adirondacks are made up of various different rocks, mostly some form of gneisse. Another common misconception is that the Adirondacks are just old, worn-down peaks like the Appalachian chain. Yes, it is true that at one point Upstate New York was at an elevation rivaling, if not exceeding, that of the Himalayas today. Known as erratics, they are picked up by the moving ice sheet and dropped when the glacier receded.
Erosion continues, exposing more and more bedrock.
Major new slides form on the flanks of the taller peaks rather frequently, sweeping away large patches of soil and vegetation. A simple glance at a topographical map will show that these faults, for the most part, all lie in a northeast-southwest orientation. Long Lake and Indian Lake, about 15 miles apart as the crow flies, run nearlyparallel to each other. These valleys, lakes, and passes exist where faults weakened the bedrock, allowing it to be more easily eroded by glaciers. We will start our hike from Marcy Dam and then set out to climb Algonquin .