Red Hills Lake County is an American Viticultural Area (AVA) located in Lake County, California and was established by the Alcohol and Tobacco Tax and Trade Bureau (TTB) on September 10, 2004. Part of the Mayacamas Range, the region lies along the southeastern shores of Clear Lake, separating Excelsior Valley to the east from Big Valley to the west. The hills lie at the foot of Mount Konocti, a volcano which last erupted 11,000 years ago, but which is still regarded as active.^[5] The terrain is rolling hills with elevations between 1,400 feet (430 m) and 3,000 feet (910 m) above sea level. Red Hills receives an average of 25 to 40 inches (635–1,016 mm) of rainfall annually.^[1][3]

The petition submitted to the TTB in 2002 was on behalf of several winegrowers, notably Beckstoffer Vineyards, Beringer Blass Wine Estate and Kendall-Jackson. At the time, there were reportedly 2,500 acres (1,000 ha) of planted vineyards in the area.^[6] By the time of the AVA establishment in 2004, there were 3,100 planted acres (1,300 ha).^[1]

In order to raise the profile of the appellation, David and Andy Beckstoffer launched in 2016 a program to incentivize reputed winemakers to use their Red Hills fruit (Beckstoffer acquired the 1,618 acres (655 ha) Amber Knolls vineyard in 1997^[7]). Each participant would receive 1 ton of Cabernet Sauvignon for free on the condition the resulting wines use the AVA and their Amber Knolls or Crimson Ridge vineyards on their labels, and be marketed in the luxury wine segment.^[8] Participating winemakers included Spoto Wines's Stuart Spoto and Lake County Brassfield Estate's Matt Hugues.

The boundaries of the AVA were modified with the establishment of the Kelsey Bench-Lake County AVA in 2013, expanding it to the northwest by 7 acres.^[9] In March 2024, following a petition on behalf of local vineyard owners, the AVA was officially expanded again, this time by 679 acres.^[10]

The most planted (and lucrative) variety in the Red Hills is by far Cabernet Sauvignon, but Cabernet Franc, Malbec, Petit Verdot, Petite Sirah are also represented,^[3] as well as Sauvignon blanc, Grenache, Mourvèdre, Syrah and Zinfandel.^[11]

Major vineyard holders in the Red Hills include Beckstoffer Vineyards, which own 4,172 acres (1,688 ha) partially planted with principally Cabernet Sauvignon (as well as some Sauvignon blanc and Malbec);^[12] E&J Gallo, which in 2014 acquired the 800 acres (320 ha) Snows Lake Vineyard;^[13] Shannon Family of Wines with their 236 acres (96 ha) Vigilance vineyard;^[14] and Obsidian Wine Company with their Obsidian Ridge vineyard.

As of May 2024, the Red Hills AVA contains three bonded wineries: Gregory Graham Wines, Laujor Estate, and Boatique Winery.