The Bern–Lötschberg–Simplon railway (BLS), known between 1997 and 2006 as the BLS Lötschbergbahn, was a Swiss railway company. In 2006 the company merged with Regionalverkehr Mittelland AG to form a new company called BLS AG.

The Bern–Lötschberg–Simplon railway was the largest standard gauge network on the Swiss Railway system apart from the Swiss Federal Railways. The railway had not been built at the time that the Federal government took control of the five big Swiss standard gauge railway companies in 1902 and so it led a separate existence, being considered the largest of the Swiss "private" railways, although the majority of its capital was owned by the cantonal government of Bern, with the Confederation holding about one fifth.

glacier Express at Brig on 17th August 2019

BLS Cargo loco 4485 017 at Brig on 17th August 2019

BLS electric 4465 003 at Spiez on 17th August 2019