The following is an incomplete list of training centres, research and development sites, administrative sites and other establishments used by the Special Operations Executive during World War II.
Numbered Stations
Establishments concerned with experimental work, storage and production were given Roman numerals (mostly in Hertfordshire). Training schools had Arabic numbers. (These included paramilitary schools around Arisaig, "finishing" schools around Beaulieu and operational schools in various counties including Gloucestershire, Leicestershire, Oxfordshire.)
Station IX - The Frythe estate near Welwyn Garden City, which began as a wireless research unit (Special Signals), then became a weapons development & production centre, then a research and development station. Now a factory belonging to GlaxoSmithKline.