The fire ruined buildings at Paramount Ranch, one of the locations used during seasons 1 and 2 of Westworld.
"Westworld is not currently in production, and as the area has been evacuated, we do not yet know the extent of the damage to any structures remaining there," HBO said in a statement. "Most importantly, our thoughts go out to all those affected by these horrible fires."
The official Twitter account of the Santa Monica Mountains National Recreation Area shared a photo of the structures as they looked before the fire, with the message, "We are sorry to share the news that the #WoolseyFire has burned Western Town at #ParamountRanch in Agoura."
Westworld was far from the only production to take advantage of the Old West-style buildings and setting for filming. Dr Quinn, Medicine Woman, the 1990s Western drama starring Jane Seymour filmed there, as well as 1968's Herbie The Love Bug, the acclaimed HBO series Carnivale and more were all filmed there.
Evan Rachel Wood, who stars as Dolores in Westworld, wrote, "This is eerie. So sad for the history lost. Amazed the church is still standing." She also noted that the sets that burned weren't the ones representing Dolores' hometown of Sweetwater. Those scenes are filmed at Melody Ranch east of Santa Clarita.
Photojournalist John Schreiber of KCBS 2 and KCAL 9 tweeted photos showing some of the destroyed buildings.
The CBS Evening News later shared video that Schreiber had shot of the burned Western Town. (CBS is the parent company of CNET.)
According to the National Park Service, Paramount Pictures purchased 2,700 acres for use as a movie ranch in 1927. Director Cecil B. Demille, comedian Bob Hope, and actors Gary Cooper and Claudette Colbert were among those who filmed there.
"The diverse landscape was the real star of the show," the park service site says. "It offered filmmakers the freedom to create distant locales such as colonial Massachusetts in The Maid of Salem (1937), ancient China in The Adventures of Marco Polo (1938), a South Seas island in Ebb Tide (1937) and numerous western locations including San Francisco in Wells Fargo (1937). The art of illusion was mastered on the landscape."
Picnickers, hikers and tourists could stroll through Western Town for free before the fire. "This real-life motion picture set is altered slightly with each production, yet retains a Western motif," the park service site says.
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