Location The site discussed here is in Thacher State Park, whichextends for 2 mi (3.2 km) along New York 157 in the extremenorthwestern corner of Albany County (Fig. 1). The Park is 13mi (20.8 km) due west of the State Capitol in downtown Albanyat 42°38'N and 74°0' W. The limestone belt is accessible by bus, passenger car, and foot, with rock exposures on both public and private lands; hammering and collecting is prohibited withinthe state park. The Helderberg Escarpment extends from Kingston (Rosendale Quadrangle, Ulster County) on the souththrough Catskill (Catskill Quadrangle, Greene County) through Thacher State Park (Berne Quadrangle, Albany County) through Schoharie (Schoharie Quadrangle, Schoharie County) to Cherry Valley (Canajoharie Quadrangle, Otsego County) (Fig. 2).