Most of Nevada lies within the Great Basin of the Basin and
Range region of North America. The rivers in the southeast
belong to the Colorado River system, while those of the extreme
north drain into the Snake. Like the Humboldt, most Nevada
rivers go nowhere, ending instead in desolate alkali
sinks—except where they have been diverted for irrigation and
reclamation, as by the Humboldt project, the Newlands project,
and the Truckee River storage project. The alkali sinks and arid
stretches clothed with sagebrush and creosote bush typify
Nevada's landscape. Its mountain chains generally run north and
south, further segmenting the state. On the California border
stand the lofty Sierra Nevada [snowy range]. In the driest state
in the nation, days and nights are generally clear. The mean
elevation is c.5,500 ft (1,676 m). In the north and west winters
reach extreme cold, while in parts of the south the summers
approach ovenlike heat. Carson City is the capital; Las Vegas is
the largest city, and Reno the second l