Sunlight Supply Amphitheater, formerly known as the Sleep Country Amphitheater and Amphitheater Northwest is an 18,000-seat capacity amphitheater, located in Ridgefield, Washington. It is the largest outdoor amphitheater in the Portland metropolitan area. It is used for concerts, stage shows and other special events, including the Clark County Fair. Construction started in 2002, with Sustaita Architects designing the venue and Hoffman Construction Company building it.