Gas Works Park on Seattle’s Lake Union transformed the former Seattle Gas Light Company plant into a public landscape that preserves major parts of the old gas works. Recommended as parkland in 1903 but developed industrially instead, the site operated from 1906 until city gas production ended in 1956. Seattle began acquiring it in 1962, and landscape architect Richard Haag’s 1971 plan preserved industrial remnants rather than clearing them, creating an unusual park that opened in 1975. Recognized locally, statewide, and nationally, it includes what is described as the United States’ only remaining coal gasification plant and stands as both a major urban park and a rare piece of industrial heritage.