Sgurr Thuilm forms part of what is known as the Glenfinnan horseshoe also taking in Sgurr Nan Coireachan. The hills lie about 6km north of Glenfinnan. Sgurr Thuilm lies at the east end of the arc with a craggy summit made up of 3 ridges. The northern ridge drops down sharply to Glen Peen passing over a subsidiary top. The south west ridge leads back to Glen Finnan. The western ridge is extended for about 3km to join up with neighboring Munro Sgurr Nan Coireachan. This ridge is knobbly throughout as it rounds the bowl of coire that these two hills surround.
The views north towards the Knoydart hills are superb throughout and you get a real sense of how remote this area is.
The horseshoe can be climbed either from the south at Glenfinnan or from the north east via Loch Arkaig. The Glenfinnan option is more accessible but will require a longer walk in, however this can be cycled easily.