Report - Unknown structure/possible AA site- istead rise, gravesend - march '11

[PeZ]

Noticed this place on the way home from istead rise one time, noticed a odd looking structure which intern i decided to investigate

The main part is round with several out buildings, looks like theres possible underground section but its filled in, further along the field there was some more concrete ruins with another possible underground section.

No history on this place but possibly AA gun post to defend gravesend airport

1. 
   http://www.bbc.co.uk/ww2peopleswar/stories/18/a4057418.shtml
   
   Gravesend Airport 1932 - 1958 | Discover Gravesham
   
   Anyway time for some pictures
   
2. 
   
   
   
   
   
   
3. 
   
   
   
4. 
   
   
   
5. 
   
   
   
6. 
   
   
   
7. 
   
   
   
   About the only feature
8. 
   
   
   
9. 
   
   
   
   Anyclue to what this is?
10. 
    
    
    
11. 
    
    
    
12. 
    
    
    
13.