I have seen on the Viewfinder Panoramas website that it is technically possible to see Criffel, Cairnsmore of Fleet and Lamachan Hill from Snowdon, although only in the most exeptional conditions. Has anyone been lucky enough to catch a rare glimpse of Scotland from the summit of Snowdon?
I know the Wicklow Mountains, Mourne Mountains and the Lake District have all seen seen, but sightings of the Scottish Southern Uplands seem elusive. The distance from Snowdon is between 131 and 139 miles.
Merrick is also technically visible (actually the longest line of sight in the British Isles) but would be very difficult to see because of Lamachan Hill being in front (only the top of Merrick would be visible). The view between Snowdon and Merrick is discussed here:
http://www.viewfinderpanoramas.org/panoramas.html#longlines