Mungrisdale Common lies north of
Blencathra of which it is an outlier. Gently graded grassy slopes fall from Atkinson Pike, Blencathra's northern summit. Upon meeting the head of Blackhazel Beck, the shoulder divides in two, the northeastern arm connecting to
Bannerdale Crags and the north western branch continuing to descend to Mungrisdale Common. Beyond an almost imperceptible depression the re-ascent is only . After the brief plateau of the summit the descent continues westward toward Skiddaw Forest. Confusingly, the forest contains no trees other than the windbreak of Skiddaw House, but it is a marshy upland area, at around , surrounded on all sides by higher fells. Three streams flow from Skiddaw Forest, dividing the Northern Fells into three sectors. Dash Beck runs north-west, the River Caldew north east and the Glenderaterra Beck south. The three ranges of the Northern Fells are the
Skiddaw massif to the southwest, the Blencathra group including Mungrisdale Common to the south east and the area colloquially known as 'Back o'Skiddaw' to the north. Skiddaw House, the lone building in the forest, has variously seen service as a shepherds' bothy and a
Youth Hostel. The Glenderaterra Beck lies to the west of Mungrisdale Common and its tributary, Roughten Gill, forms the southern boundary. A further feeder on this flank is Sinen Gill, whose
waterfall is one of the fell's most notable features. The River Caldew lies to the north, across which is
Great Calva, most southerly of the Back o'Skiddaw fells. Despite its uninspiring appearance Mungrisdale Common does therefore stand on the important
Eden-
Derwent watershed, though it is not well defined at this point. Water from the southern flanks reach the sea at
Workington while rain falling on the northern side heads for the
Solway Firth via
Carlisle. The watershed continues across Skiddaw Forest between the headwaters of the Caldew and Glenderaterra, linking onward to
Lonscale Fell in the Skiddaw range. Mungrisdale Common carries a very small
cairn at the approximate summit, constructed only after Wainwright first encouraged climbing of the fell by including it in his 1962 guidebook. Two more prominent ancient cairns also grace the fell, one to the west of the summit and the other on a tongue of ground between Sinen Gill and Roughten Gill. A small stone pillar (marked 'stake' on
OS maps) stands on the watershed at the head of Glenderaterra Beck and a further prominent Cloven Stone marks its continuation higher up the slope. Both have served as boundary stones. ==Geology==