Are seat reservations required with the Bernese Oberland Rail Pass?

As a rule, seat reservations are not required on trains, buses, ships and mountain railroads. It is recommended to reserve a seat on the Jungfraujoch. Tickets to the Jungfraujoch are subject to a quota. The connecting ticket to the Bernese Oberland Regional Pass and seat reservations are available online at store.jungfrau.ch or at all Jungfrau Railway stations.