The peak of Helvellyn is the highest on the north-south ridge situated between the Thirlmere valley to the west, and Patterdale to the east. This ridge continues north over Helvellyn Lower Man, White Side, Raise, Stybarrow Dodd, Great Dodd and Clough Head, and south leads to Nethermost Pike and Dollywaggon Pike
The eastern side of the fell is geographically the most dramatic. Two sharp arêtes lead off the summit, Striding Edge and Swirral Edge, either side of Red Tarn. The knife-edged Striding Edge provides one of the best-known scrambles in Lakeland, while the Swirral Edge ridge leads to the conical summit of Catstye Cam.
Nestling between the encircling arms of Helvellyn's two edges, is Red Tarn. This pool is named for the colour of the surrounding screes rather than its water, and contains brown trout and schelly, a fresh-water herring. The depth of Red Tarn is now about 80 feet (25m), although in the mid-19th century it was dammed with boulders to increase capacity. This was carried out to provide additional water to the Greenside lead mine in Glenridding, the water race still visible as it crosses the slope of Birkhouse Moor.
A second tarn once existed in Brown Cove between Swirral Edge and Lower Man, but this now is reduced to a couple of small pools widening the stream. Brown Cove Tarn was another creation of the Greenside mine, a stone-faced dam being built in about 1860. The dam is still in place, but water now leaks through the base, the extended tarn-bed a smooth patch of luxuriant turf. A water leat passing beneath the north face of Catstye Cam to Red Tarn Beck can still be traced, although it is now in ruins. Water from Brown Cove and Red Tarn unites at the beyond Catstye Cam to form Glenridding Beck, flowing on through the village to Ullswater.
The western slopes are relatively shallow, and partially forested, with many gills leading down to the Thirlmere valley.