EGGL was originally allocated to Lulsgate
Pre-c.1960 the UK civil location indicators began with G, and the mil with M, eg.
GALA was Heathrow ('London Airport') > EGLL (Switching centre)
GABA Croydon aerodrome (as opposed to the Civil Aviation Comms Centre)
GAOA Blackbushe > EGLK
GASA Eastleigh > EGHI
GASU Portsmouth > EGHP
GASR Hamble > EGHM
GAUA Hurn > EGHH (Switching centre)
GAVA Lulsgate > EGGL > EGGD
Some Hampshire military:
MAXF Farnborough
MAYO Odiham
MAZL Lasham
Whilst we are on letters, some of the RAF aircraft, usually transport, used five-letter callsigns which were occasionally painted on the nose.
eg. the RAE Comet was MPDXA. MOBCY was a Beverley. Maybe some more will come to me in the middle of the night...
I liked the call from the Amsterdam-Ronaldsway Viscount routing from 'Ham to Eggs'