Notice the stone wall that runs parallel to the railroad at the bottom of the slope. At one time much of NH was dedicated to pasturing sheep to provide wool to the mills in Manchester and Lawrence. The stone wall was likely the edge of a pasture that has now returned to forest. In another 50 feet along the trail to the east you will be crossing over the natural gas line that feeds the Granite Ridge power plant. The gas line traverses the entire length of Londonderry from the Windham line to the Manchester line. It forms a wildlife corridor that joins the forest you are in now to other natural areas within the town.