Excuse rush, Bill - typing in a hurry before leaving for airport & vacation : -
Not as much remains to be seen as, say, 20 years ago when there was a lot to be found

You now really do have to 'know where to look'.
The good news is that, due to the efforts of dedicated volunteers and renewed public interest, some very fine museums have been created using restored control towers and other buildings, such as those at Framlingham, Boxted and ( especially ) Thorpe Abbotts. For anyone interested in 8th history, Thorpe is an absolute
must !
http://www.controltowers.co.uk/T-V/Thorpe_Abbotts.htm