---
alias:
- RAF Menwith Hill
- Menwith Hill Station
category: Military Installation
created: 2026-09-22
location: North Yorkshire, England
summary: The NSA's largest field station, on the Yorkshire moors near Harrogate, ground
  station for the CHALET and VORTEX signals satellites and a node of ECHELON, where
  the Lockheed software manager Margaret Newsham said she listened to intercepted
  telephone calls in the early 1980s.
tags:
- Place
- MenwithHill
- NSA
- GCHQ
- ECHELON
- SIGINT
- UnitedKingdom
updated: 2026-09-22
---

Menwith Hill, in North Yorkshire near Harrogate, is "NSA's largest field station in the world," in the words of Duncan Campbell's 1999 report to the European Parliament, "responsible for operating over 250 classified projects" under three directorates. It became the ground station for the CHALET, VORTEX and MERCURY series of signals intelligence satellites, chosen "under NSA project P-285" and launched in June 1978 and October 1979, with the STEEPLEBUSH operations centre built to process their take; after 1985 its mission expanded to the [Middle East](/places/middle-east/), it was commended for support to naval operations in the Gulf in 1987 and 1988 and to Desert Shield and Desert Storm in 1991, and by the late 1990s it was, in Campbell's account, "the major US site for Comint collection against its major ally, [Israel](/places/israel/)," staffed with Hebrew, Arabic and Farsi linguists; ground links for a new satellite class, RUTLEY, were added in 1994 and 1995. "A senior UK Liaison Officer and staff from [GCHQ](/organizations/gchq/) work at Menwith Hill NSA station and assist in tasking and operating the satellites." Nicky Hager, who counted 22 satellite terminals and over two hectares of buildings, called it "undoubtedly the largest station" of its kind in the [ECHELON](/programs/echelon/) network, alongside [Pine Gap](/places/pine-gap/) and Bad Aibling.[^1][^2]

### Newsham

Margaret Newsham, a Lockheed Space and Missiles contract employee who was "software manager for more than a dozen VAX computers at Menwith Hill which operate as part of the ECHELON system" until the mid-1980s, told congressional staff that she had listened through earphones to monitored telephone calls at the station; her account followed a July 1988 story in the Cleveland Plain Dealer alleging that the calls of Senator Strom Thurmond had been intercepted. [Sean McDade](/people/sean-mcdade/), the Canadian investigator of the [PROMIS](/programs/promis/) affair, said he was a target of ECHELON while working in the United States in 2000.[^2][^3]

[^1]: Campbell, Duncan. *Interception Capabilities 2000,* report to the European Parliament's STOA panel, April 1999, paras. 8, 38-39, 42, 44. https://irp.fas.org/eprint/ic2000/ic2000.htm
[^2]: Hager, Nicky. *Secret Power: New Zealand's Role in the International Spy Network,* Craig Potton, 1996, chs. 2-3. https://archive.org/details/hager-nicky-secret-power_202012
[^3]: House Report 102-857 (1992) and the Bua report (1993), searched in full, contain no reference to the station; Seymour, Cheri, *The Last Circle,* TrineDay, 2010, as cited on [[Sean McDade]].