Some history from subbrit:
"This bunker is located at the side of Road of Remembrance in Folkestone, dug directly into the cliff face. As with many bunkers of this type, no documentary evidence can be traced of its origins or use. It is believed, however, to be a WW2 Naval communication facility. The tunnels are lined throughout in concrete, and there are many partitioned rooms, retaining original paintwork, doors and other features, including the remains of some wartime posters. Toilet facilities also exist, at street level behind the main entrance, the rest of the rooms being down a set of stairs. Above the entrance to the bunker is a ventilation plant room. The bunker does not appear to have been used since the war, and the main doors have remained sealed for a number of years."
Started off by going for the biggest hole on the West side - turns out that it has a lot of rusted drums with no access to the bunker itself. On my second attempt, after getting my bag through the hole, I followed suit, getting covered in rubble and sand in the process. Not as much of a squeeze as the window at St Mary's Westbrook, but involved some ninja skills once through the opening.
There was another odd little tunnel like this on the opposite side. Didn't go anywhere though.
There were a couple of rooms like this, unfortunately pretty much everything from the war was long gone, with some graffiti replacing it.
The overhead metal pipe things had mostly came away from the roof throughout the whole bunker.
An old piece of electrical equipment, disconnected.
No chair shot available, so the best alternative was a bog shot.
The door above opened really smoothly, kind of surprising the hinges worked so well after 70 years.