S21 (RER Fribourg)

The S21 is a railway service of RER Fribourg that provides hourly service between Ins and Romont FR, in the Swiss cantons of Vaud and Freiburg, respectively. Transports publics Fribourgeois operates the service.

S21
Overview
First service	14 December 2014 (2014-12-14)
Current operator(s)	Transports publics Fribourgeois
Route
Termini	Ins Romont FR
Stops	17
Distance travelled	51.7 kilometres (32.1 mi)
Average journey time	1 hour 22 minutes
Service frequency	Hourly
Line(s) used	Fribourg–Ins line Lausanne–Bern line
Route map Legend Regional services to Travers Regional services to La Chaux-de-Fonds Regional services to Yverdon-les-Bains 42.9 Neuchâtel S20 S5 36.7 Marin-Epagnier S20S5 32.2 Ins S5 S20 S52 Regional services to Biel/Bienne S5 S52 to Kerzers 27.8 Sugiez S20 S5 S52 to Bern 24.2 Muntelier-Löwenberg S5 22.2 Murten/Morat S5 S52 R9 S20 S5 S52 R9 to Payerne 20.6 Münchenwiler-Courgevaux S20 16.9 Cressier FR S20 12.4 Courtepin S20 9.2 Pensier S20 5.8 Belfaux-Village S20 S30 S30 to Payerne 4.0 Givisiez S20 S30 S30 S1 to Bern 0.0 66.0 Fribourg/Freiburg S1 S40 S41 to Lausanne [1][2] This diagram: view talk edit

Operations

The S21 runs hourly between Ins and Romont FR. It uses the western end of the Bern–Neuchâtel line, the entirety of the Fribourg–Ins line, and a portion of the Lausanne–Bern line. It is paired with the S20 between Ins and Fribourg/Freiburg, and between Ins and Romont FR on weekdays, providing half-hourly service.^[3][4]

History

RER Fribourg introduced the S21 designation on 14 December 2014 for a rush-hour service between Fribourg and Kerzers.^[5] In December 2017 it was changed to an hourly service on weekdays between Fribourg and Ins, paired with the S20 and together providing half-hourly service.^[6] With the December 2021 timetable change, both the S20 and S21 were extended south from Fribourg to Romont, replacing the S40.^[7] The S21 began running on weekends with this change, while the S20 operated between Fribourg and Romont on weekdays only.^[8]