Ullscarf is bordered on the west by the Greenup valley, with steep but mainly grassy slopes, the chief exception being Lining Crag. This impressive rock face is prominent in views up the valley, standing right beside the bridleway. From above however it is reached via a shallow grassy saddle and makes a fine viewpoint or picnic spot. A number of gills run down this western side of Ullscarf. To the east lies Thirlmere across a moorland of small hillocks. The final descent is steep, falling down conifer clad slopes to the reservoir. To the south of Thirlmere is its feeder valley of Wythburndale, which rises eastward to its source below Greenup Edge. Above Wythburndale Ullscarf displays a near continuous line of crags, the principal faces being Castle Crag and Nab Crags. A series of low tops crown the edge above Nab Crags, one of them bearing a prominent stone structure visible from the valley below. This is marked 'beacon' on OS maps, but is in fact a very short length of dry stone wall. It was set up some decades ago to replace a vandalised beacon cairn. The main ridge of the Central Fells continues south from Ullscarf, dropping over a field of rocky knolls to cross the wide depression of Greenup Edge. This is the connection to High Raise, the highest of the Central Fells. To the north, the natural boundaries are unclear. Standing Crag provides a terminal to the summit plateau, rising beautifully above its reflecting tarn. From here the ridge continues across wet ground toward High Tove, the next Wainwright. Some guidebooks however consider the intermediate Bell Crags to be a separate fell. A second subsidiary ridge travels north north west from the summit to Great Crag, passing over the twin tops of Coldbarrow Fell. Between these two northern ridges is Blea Tarn. A large pool of about depth, Blea Tarn provides the main feed for the more famous beauty spot of Watendlath Tarn. Drainage to the east is provided by Ullscarf and Launchy Gills, the former flowing via the secluded Harrop Tarn within the Thirlmere Forest. This may be a corrie tarn which has silted up over time, extensive shallows being colonised by sedge, water horsetail and yellow water lilly. These waters are joined by the Wyth Burn from the south of the fell. All water from the west of the fell reaches Greenup Gill via a number of feeders and flows to Derwentwater.
Geology
The summit area is composed mostly of till overlying rocks of the Lincomb Tarn Formation. This consists of dacitic lapilli-tuff with andesite sills. The eastern plateau above Thirlmere shows some outbreaks of the volcaniclasticsandstone of the Esk Pike Formation. A 16th century mine, Launchy Gill Level, was driven into the fellside below White Crags on the Thirlmere side of the fell. A scramble is required just to reach the mouth of the level.
Summit
The top of the fell is an upland plateau of about, predominantly clad in coarse grass and heather. There are few paths on the fell itself. One track follows the watershed, being marked in places by old iron fenceposts. Bridleways cross the ridge to the north and south of Ullscarf, providing access from Wythburn, Thirlmere, Stonethwaite and Watendlath. The summit is marked by a large cairn on a small rocky outcrop, the old fenceposts marching past in either direction. Views from the top are extensive, befitting the central location, with the Scafells and Helvellyn ranges being shown to particular effect.
Ascents
From Wythburn to the south east a number of routes are possible. The Wythburn valley can be followed to reach the ridge at Greenup edge, or more direct climbs can be made via Harrop Tarn. From here either the line of tops above Nab Crags or Standing Crag will be the intermediate objective. Ullscarf can be climbed from Watendlath, gaining the north-north-east ridge above Blea Tarn, and then ascending over the tops of Coldbarrow Fell. The most-used route, since it coincides with a section of Wainwright'sCoast to Coast Walk, is to follow the Greenup valley from Stonethwaite, passing up beside Lining Crag and then turning north before Greenup edge to 'cut the corner'.
