The Cold War upgrades of the WAB, BOB, JB, BLM, SPB, HB, DIH, TSB and Brünigbahn railways

Ovieview
They travel through the Swiss Alpine pastures of the Bernese Oberlan. and around or over the imposing peaks of the Eiger, Mönch and Jungfrau. The lines opened, using steam traction, in late Victorian times and were electrified in the 1910s.

Jungfraubahn (JB)

 * 1937 The Sphinx Observatory is opened. A snowblower is purchased and this results in year-round operation.
 * 1942 Relocation of the company offices from Zürich to Interlaken.
 * 1950 The dome is installed on the Sphinx Observatory.
 * 1951 The adhesion section between Eismeer station and Jungfraujoch station is converted to rack operation.
 * 1955 A second depot at Kleine Scheidegg is constructed. The post office inaugurates its relay station on the Jungfraujoch.
 * 1972 The panoramic windows are installed at Eigerwand and Eismeer. The Jungfraujoch mountain house and tourist house are destroyed by fire on 21 October.
 * 1975 A new tourist house is opened.
 * 1987 A new mountain house is opened on 1 August.
 * 1991 A new station hall is opened at the Jungfraujoch.
 * 1993 The small Kleine Scheidegg depot is extended.

Bernese Oberland Railway (BOB)
Several changes were made during the 1950s and 1960s, the two most important being in 1957, the construction of an airfield at Interlaken causing the realignment of the line between Wilderswil and Interlaken Ost, but to no detriment and, with a need for servicing and construction facilities on the line a new depot was opened at Zweilütschinen in 1968.