Vermilion River Observatory

The Vermilion River Observatory was a radio astronomy research facility in Danville that used a large parabolic telescope built into a natural ravine. The structure stretched roughly 600 feet long and was covered with asphalt and wire mesh to collect signals from space.

The University of Illinois built this facility in 1959 under Professor George Swenson with support from the Office of Naval Research. The observatory operated for about 25 years before closing in 1984.

The facility attracted astronomers working to understand our galaxy's structure and cosmic phenomena through radio signals. Researchers here made discoveries that shaped how we view the universe today.

The site sits in a natural ravine outside Danville and is not easy to reach, as the facility is no longer active. Visitors should know the structure is heavily overgrown and located in a quiet, remote area.

Engineers cleverly used the natural ravine's slope to reduce construction costs and fit the telescope directly into the landscape. This resourceful approach allowed them to build a large instrument without expensive additional structures.

Location: Illinois

Inception: 1959

Official opening: 1959

GPS coordinates: 40.06111,-87.56111

Latest update: December 12, 2025 17:48