The Gastern Valley , also Gasterental or (according to the Swiss National Map) Gasteretal , is a valley near Kandersteg in the Bernese Oberland . It is flowed through by the Kander . The rear basin is about 1600 m, the valley exit about 1350 m high. The valley is inhabited only during the summer months.
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A beautiful forest , which for centuries has resisted the avalanches of the Doldenhorn , and a chaos of rocks through which the Kander flows are now traversed.
1 hr. Gasternholz (4462 ′) . Traces of avalanches become more perceptible as we descend. The valley forms a curve, and expands, being bounded on the S. by the huge Altels ( 11,922 ) , and on the N. by the Fisistock (9200′) . The Gastern -Thal was much more thickly peopled at the beginning of the century than now, the indiscriminate felling of timber having so exposed it to avalanches, that the inhabitants are compelled to abandon it from the month of February to the hay-harvest . The Kander here forces its passage through the --
1 hr. Klus , a narrow gorge , beyond which we reach the valley of the Kander and the Gemmi route.

Bædeker Switzerland (1877) Route 64 page 268