The story
STI was formed in December 1911, originally as the Elektrische Bahn Steffisburg-Thun-Interlaken (English: Steffisburg–Thun–Interlaken Electric Railway), and began carrying passengers on 10 October 1913, with the opening of a tram line between Steffisburg and Oberhofen (via Thun), which was later extended to Beatenbucht and finally to Interlaken. Plans for road rebuilding led to the closure of the Beatenbucht–Interlaken section of tramway in 1939, but trams continued to provide the Thun–Beatenbucht service, STI's main line, until 1952. The Thun–Steffisburg tram line closed in 1958, and since then the STI network has been covered exclusively by buses. Trolleybuses, powered by electricity drawn from overhead wires, were used on the main line, Thun–Beatenbucht, connecting at Beatenbucht with the Thunersee–Beatenberg funicular and with a motorbus route covering the section to Interlaken. In 1982, the trolleybuses were replaced with conventional, diesel-powered buses. STI introduced its first night service in 1993, between Thun and Bern called the Moonliner. Further extensions made to the network in 1999 and 2001 took STI buses into areas such as Gwatt, which had seen railway station closures. In 2022, STI moved headquarters to the Cremo building in Schwäbis.
From Wikipedia’s article on Verkehrsbetriebe STI, shared under CC BY-SA 4.0.4