 These take over shortly after the contour is crossed again, and the mountain's southern summit offers a sweeping panorama of the Catskills that has been considered by many to be one of the best views in the region.Slide Mountain and all the major peaks around it are visible across the flat valley of Esopus Creek and Ashokan Reservoir in central Ulster County.Close up loom Twin's true northern summit and Sugarloaf Mountain.