The miniaturesheet is an artists composition of different elements.
The background is showing an areal view from the Lötschen Valley towards Lötschenlücke and major peaks of the Bernese Alps with its highest summit, the Finsteraarhorn at 4'274 m. Part of the miniaturesheet are four historic pictures (black-white) of the Swiss Alpine Museum in Bern. The old picture at the top-right was taken by Robert Schönbächler and is showing the SAC Leutschachhütte, before the hut was renovated.
The building on the 1.90 value stamp (bottom) is an artists composition and symbolizes the 152 mountain huts (2013) of the Swiss Alpine Club.
Many thanks to Fredy Trümpi (designer of this miniaturesheet) for the detailed information.