Remarkably, I've never visited SAS's global HQ in Cary, North Carolina. From what I've seen and read, it's quite some place. I've driven past it whilst visiting clients in the Research Triangle Park (RTP) area, so I have some conception of the size of the estate.
SAS UK's HQ is not as large, but it's pretty grand. Take a look at this PDF to see some nice pictures and to understand the history of the Thames-side, 110 acre estate, located west of London. Originally owned by Lord Devonport who made his fortune from tea, the house features its own ghost: the "grey lady".
I'm told that part of the deal to buy the adjacent land in 1997 was a promise to retain the cricket pitch and its availability for the local village cricket team. True to their word, SAS have restored the pitch, built a new pavilion, and made all of this available to SAS staff, the local cricket team, and the local Scout group.
In SAS's care since 1985, a visit to Wittington house is always a pleasure.