Mullard Radio Astronomy Observatory

The Mullard Radio Astronomy Observatory stands east of Cambridge on a former ordnance storage site near Harlton. It occupies land once used by the Lords Bridge Air Ammunition Park and the disused Oxford–Cambridge railway line. The observatory was founded by the University of Cambridge’s Cavendish Laboratory and opened in 1957 by Sir Edward Victor Appleton. Martin Ryle led its early development as part of the Radio-Astronomy Group. Today it houses some of the world’s largest aperture synthesis radio telescopes. The site is recognised for pioneering radio interferometry in the mid-1940s. Funding included a £100,000 donation from Mullard Limited, a valve manufacturer. The One-Mile Telescope and 5-km Ryle Telescope were built here using sections of the old railway track bed. The Cavendish Astrophysics Group continues to operate the observatory. Its work remains central to advances in radio astronomy. Visitors find a quiet landscape of telescopes arranged across open ground. The telescopes stand beside remnants of the old railway line, now repurposed for astronomy. The site is bordered by farmland and the remains of the ordnance depot. There are no public viewing areas, but the telescopes themselves form a striking sight. The atmosphere reflects both scientific purpose and the observatory’s historic setting.