Goldendale Observatory State Park is an educational facility on the northern side of Goldendale, Washington, notable for its unusually large public telescope. The state park occupies atop a hill. Access is via a winding paved road through an oak forest. The site includes a small picnic area, interpretive center, amphitheater, and the observatory. There are several telescopes on-site, including portable Dobsonians, a permanently mounted Hydrogen-Alpha solar telescope, and the primary instrument; a 24.5-inch reflector which is housed in the South Dome. The facility receives 30-40,000 visitors annually. From 2010 to 2017 the park was an International Dark Sky Park, and expects to be a dark sky site again when the current observatory reconstruction is completed. History The main 24-inch telescope is the reason for the existence of Goldendale Observatory and was the work of four amateur astronomers — M.W. McConnell, John Marshall, Don Conner and O.W. VanderVelden — who built a Cassegrain reflecting telescope for Clark College in Vancouver, Washington, which paid for the materials to make the telescope. At the time, this instrument was one of the largest amateur-built telescopes in the world. However, once built, the college sought a clearer, darker area to install the telescope due to light pollution from Vancouver and nearby Portland, Oregon, and the typically wet and cloudy weather on the windward side of the Cascade Mountain Range. While traveling through Goldendale, Washington, the telescope builders met a local diner owner and city council member who suggested they donate the telescope to the town. An agreement was made and the telescope was donated by the college to Goldendale on the condition that the community would build an observatory to house the telescope. A local, non-profit organization was created to plan and support the observatory which was ultimately constructed one mile (1.6 km) north of the town center using donations, loans, and a $135,000 grant from the Economic Development Administration. The Observatory design was based on the University of Washington's Manastash Ridge Observatory built west of Ellensburg in 1972. Unlike that facility, the intent of the founders and community college was for Goldendale Observatory to serve primarily as a center of public science education. The Observatory was built over a period of several months and dedicated on October 13, 1973. The south observatory dome has a diameter of , and the north dome a diameter of . The observatory served as the Astronomical League's official