The Kashyyyk oil refinery, situated close to the city of Kachirho on the planet Kashyyyk, was a notable construction. During the Battle of Kashyyyk, the Separatist military tried, without success, to obliterate the refinery in an effort to deprive the Wookiees of their fuel resources.
Before its initial canonical depiction in Star Wars: Galactic Defense, the refinery had already been shown in Star Wars: Battlefront II, a Star Wars Legends video game.