I remember being shown this OB as a child back in the 1970s by a family friend, possibly an original member of the patrol, John Henry Thomas. Approached down an unmetalled track, a public right of way, with a wooded area to the south rich in native bluebells the track is soon dominated by a steep bank to the north. Part way down a cutting has been made into the bank about the size of a truck. On the top of the slope above this and to the west was the main OB entrance via a vertical brick lined shaft / chamber covered at the time with old sheets of corrugated tin. The alternative entrance was a horizontal tunnel terminating in the bank some distance along the footpath adjacent to a fence and style giving onto an open area of land with stream fed by a fresh water spring (our source of wild watercress at the time)
I returned some time in the 1990s but the bank had been machine-cleared and there was no sign of the main entrance remaining.
Hi Mike, many thanks for posting the information regarding the Reydon Patrol. We (Evelyn and I) did find it and have recorded it. It should be up on the site very soon. However we are interested that you say the shaft was brick lined, we could find no trace of bricks whatsoever and would be interested to confirm that the one you found was indeed the Reydon Patrol's OB. Those in south Suffolk were all built by the men themselves and were quite primitive in their construction, with flat corrugated iron roofs and the entrances and exits were also usually lined with corrugated iron in the same manner. I would appreciate it if you would contact me direct with a grid reference or name for the lane which you describe just incase there were two. The rest of your description matches the description very well, including the fact the site has been virtually cleared. This was the result of Dutch Elm Disease which affected all the elm trees which were removed by the landowner between the dates which you were there.
Kind regards, Adrian.