“The Ongoing Exploration of McFails Cave” at Thacher Visitor Center. 2 p.m. McFails Cave in Schoharie County is the longest known cave in the northeast United States, with over seven miles of mapped passage.  Known in the 1940s as one of the lesser caves of Schoharie County, its continuing exploration is a case study in the extremes to which cavers will go to discover new passage. Call 518-872-0800 for more information.