California State Route 190 California State Route 190 State Route 190 (SR 190) is a state highway in the U.S. state of California that is split into two parts by the Sierra Nevada. The western portion begins at Tipton at a junction with State Route 99 and heads east towards Porterville before ending at Quaking Aspen in the Sequoia National Forest. The eastern portion begins at US 395 at Olancha, heads east through Death Valley National Park, and ends at State Route 127 at Death Valley Junction. The 43.0-mile (69.2 km) portion over the Sierra Nevada remains unconstructed, and the California Department of Transportation
Geology of the Death Valley area laterally over the surface, laying down cobbles, sand, and mud. Outcrops of the resulting conglomerates, sandstone, and mudstone of the Titus Canyon Formation can be observed in road cuts at Daylight Pass on Daylight Pass Road, which becomes State Route 374 a short distance from the pass. Several other similar formations were also laid down. Large volcanic eruptions, originating near the Nevada Test Site, covered the Death Valley area and much of Nevada in thick sequences of silica-rich ash 27 million years ago. The ash has a rhyolitic composition, which is the volcanic equivalent of the plutonic rock granite; it