The Rattlesnake Hills form the northern edge of the Yakima Valley, running from the vicinity of Benton City to just south of the city of Yakima, where the Yakima River cuts through the mountain ridge via Union Gap. To the west of the Yakima River the mountain ridge is known as Ahtanum Ridge.
Roza Canal, used for agricultural irrigation, passes under the Rattlesnake Hills through a tunnel.
Named high points of the Rattlesnake Hills, according to the USGS, include Elephant Mountain, Zillah Peak, Eagle Peak, High Top, Lookout, and Rattlesnake Mountain.
Shaded-relief map showing ridges of the Yakima Fold Belt of south-central Washington. The box on right is the Tri-Cities, Washington, and the ridge north of the Yakima River (directly west of the Tri-Cities) is what is often called the "Rattlesnake Hills".
Rattlesnake Hills AVA
Pinot Noir grapes in May in the Rattlesnake Hills AVA. The Rattlesnake Hills lie in the background.
The Rattlesnake Hills AVA is an American Viticultural Area located in Yakima County and Benton County, Washington in Washington state. United States Alcohol and Tobacco Tax and Trade Bureau (TTB) awarded Rattlesnake Hills its appellation status on March 20, 2006, making Rattlesnake Hills Washington's ninth federally recognized American Viticultural Area. The Rattlesnake Hills AVA is entirely contained within the Yakima Valley AVA, which is in turn is entirely contained within the larger Columbia Valley AVA. The hills form the northern boundary of Yakima Valley, and the AVA includes land between the north bank of the Sunnyside Canal and the entirety of the southern slopes of the Rattlesnake Hills between Outlook and the Wapato Dam. The AVA is centered on the city of Zillah. With elevations ranging from 850 feet (259 m) to 3,085 feet (940 m), this AVA contains the highest point in the Yakima Valley AVA.[6]
The Rattlesnake Ridge is one of the larger "folds" in the Yakima Fold Belt. The Yakima Fold Belt is an area of topographical folds (or wrinkles) raised by tectonic compression. It is a 14,000 km2 (5,400 sq mi) structural-tectonic sub province of the western Columbia Plateau Province resulting from complex and poorly understood regional tectonics. The folds are associated with geological faults whose seismic risk is of particular concern to the nuclear facilities at the Hanford Nuclear Reservation (immediately north of the Rattlesnake Hills) and major dams on the Columbia and Snake Rivers.
As of January 21, 2018, a large but slow landslide is occurring in the Rattlesnake Hills, about 3 miles south of Yakima in Washington, USA. The event first drew news coverage in late 2017, after a long fissure was discovered high on Rattlesnake Ridge: this fissure was reported to be 250 feet deep in one place.[14] The first road closure for public safety was reported on December 17, 2017. The Washington State Department of Natural Resources has a web-page providing information on the event, which reports that the moving mass of basalt is about 4 million tons, covering about 20 acres, and it is slipping roughly south at a rate of about 1.5 feet per week.[15]
On the weekend of January 20–21, 2018 there was flurry of new reporting, which highlighted a developing consensus that the landslide will at some time collapse suddenly, and that is likely to occur within months if not weeks.[16][17][18][19][20]
^"To Prevent a Nuclear Disaster, Washington Firefighters Burned a Whole Mountain". Vice. Retrieved 2022-04-21. The raging inferno, called the Range 12 Fire, threatened to summit Washington's Rattlesnake Mountain, and creep down the other side toward the Hanford Nuclear Site, an aging nuclear production complex that sits along the Columbia River.
