Hat Creek Radio Observatory

Hat Creek Radio Observatory (HCRO) is a working radio-astronomy campus at 42231 Bidwell Road in Hat Creek, California, operated by the SETI Institute. It is home to the 42-antenna Allen Telescope Array, designed for SETI research and also used for advanced radio astronomy, alongside other site instruments. HCRO offers a self-guided tour during current Thursday-Friday visitor hours, but SETI identifies it as an active research site and requires visitors to turn off cell phones and GPS equipment so they do not interfere with operations. Check current hours and access guidance before travel; visitor access does not imply entry to every operational area.