Key
| Heavy Anti-Aircraft Site |  | Airfield |  |
| Radar Station |  | Ordnance Factory |  |
| Site No. | Name | OS Grid Reference |
| BY1 | Amersham | SU 681 693 |
| BY2 | Tilehurst | SU 676 741 |
| BY3 | Tanners Farm | SU 708 771 |
| BY4 | Sonning | SU 772 754 |
| BY5 | Toutley | SU 797 705 |
| BY6 | Crockers Farm | SU 751 700 |
Coding sequence integral with Aldershot, Basingstoke & Guildford
Gun Strengths
Overlord & Diver
| Dates | 3.7 inch static |
| Apr-Aug 44 | 8 |