The area's reputation suffered a major blow in the early 1880s when Arnold Henry Guyot, an occasional visitor, undertook to do in his spare time the first complete survey of the Catskills and found that, contrary to the claims of Beach and other hoteliers in the area, the highest mountain was not nearby Kaaterskill High Peak, which dominates the view south over the lakes, but Slide Mountain, some distance to the southwest in the Ulster County town of Shandaken. They at first disputed this claim vigorously and even tried to cast aspersions on Guyot's reputation, but by 1886 his results had been confirmed by others and the North-South lake region had lost some of its cachet.