
Surprise Valley and the expansive basin of Middle Alkali Lake define this high-desert region of Modoc County. The geography is marked by the seasonal and thermal hydrologic features characteristic of the Great Basin edge, most notably the namesake Leonards Hot Springs. Seasonal drainages like Sand Cr and Fortynine Cr descend from the eastern heights into the valley floor, carving distinctive landforms such as Fortynine Canyon.
12 named features on this map. Tap any name to fly to it.
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This is the sole edition of this map. No revisions or reprints were ever made.
1886 · Alturas
USGS Topo · 1:250,000
1889 · Long Valley
USGS Topo · 1:250,000
1892 · Alturas
USGS Topo · 1:250,000
1954 · Vya
USGS Topo · 1:250,000
1954 · Alturas
USGS Topo · 1:250,000
1958 · Alturas
USGS Topo · 1:250,000
1958 · Vya
USGS Topo · 1:250,000
1962 · Alturas
USGS Topo · 1:250,000
1962 · Vya
USGS Topo · 1:250,000
1962 · Cedarville
USGS Topo · 1:62,500