He made several first ascents in the Alps, including Piz Scerscen with Hans Grass and Caspar Capat on 13 September 1877 via the north-west spur (the Eisnase route). On 12 August 1878, Hans Grass, Johann Gross and he first climbed the Biancograt north ridge of Piz Bernina. He made winter ascents of the Grandes Jorasses and the Gran Paradiso, as well as putting up several new routes on Mont Blanc, including the Peuterey ridge on 15-19 August 1893 (with Emile Rey, Christian Klucker and César Ollier). Pointe Güssfeldt (4,112 m), the highest summit on the Aiguille Blanche de Peuterey is named after him, as is the Güssfeldtsattel, the col between Piz Scerscen and Piz Roseg also known as the Porta da Roseg. This steep ice slope was first climbed by Güssfeldt with guides Hans Grass, Peter Jenny and Caspar Capat on 13 September 1872.