August 17, 1878 Saturday – While Sam rested, smoked and wrote letters in Lucerne, Joe Twichell went solo on a three-day trip in the Alps, to St. Gottard Pass. (Day By Day)

The Gotthard Pass or St. Gotthard Pass (Italian: Passo del San Gottardo, German: Gotthardpass) at 2,106 m (6,909 ft) is a mountain pass in the Alps traversing the Saint-Gotthard Massif and connecting northern and southern Switzerland. The pass lies between Airolo in the Italian-speaking canton of Ticino, and Andermatt in the German-speaking canton of Uri, and connects further Bellinzona to Lucerne, Basel, and Zurich. The Gotthard Pass lies at the hearth of the Gotthard, an important north-south axis in Europe, and is it crossed by three major traffic tunnels, each being the world's longest at the time of their construction: the Gotthard Rail Tunnel (1882), the Gotthard Road Tunnel (1980) and the Gotthard Base Tunnel (2016). With the Lötschberg to the west, the Gotthard is one of the two main north-south routes through the Swiss Alps. Since the Middle Ages, transit across the Gotthard played an important role in Swiss history, the region north of Gotthard becoming the nucleus of the Swiss Confederacy in the early 14th century.
Wikipedia

See Bædeker Switzerland (1877) Route 25 page 90