The Thumbnail is a sea cliff in Kujalleq, South Greenland.
The nearest peak dominating the neighboring ridge is Agdlerussakasit (1760 or 1706 m a.s.l.)
In 2000, 2003 and 2007 there were established 4 climbing routes on the east face, all starting from the sea.
The hardest one is the earliest, British route, established in the steepest, right-hand part of the face in 2000 and graded as English E6, 6b or American 5.12c.
The route finishes on the subsidiary top/outcrop (which was in 2000 called as Thumbnail itself) and has altitude approximated by altimeter as 1350 meters a.s.l.