Citing fears of a hazardous traffic overload, state officials will ban roadside parking along the entrances to a pair of popular Adirondack trails during the Columbus Day weekend, instead directing hikers to a large lot nearly three miles away.The parking ban will cover roadside spots along Route 73, which runs between the Adirondack Northway and Lake Placid.Cars will not be allowed to pull off and park near the trailheads for Cascade Mountain, Porter Mountain, and Pitchoff Mountain from Oct.