Category Archives: Underground

Canterbury Bunker, Kent

6th MayThe Canterbury Bunker is an old underground Brigade Command Center that was decommissioned around 1945. The owner had previously found and opened up the west entrance with the help of KURG and this return visit was to explore the newly opened up east entrance. When the first entrance was opened up, the passage having been completely sealed for many years, was full of bad air from rotting wood and had to be well ventilated before exploring was possible. The air in the east passage was well ventilated before we entered and presented no problems
The west entrance, an opening near ground level, leads down a flight of 59 steps then along through an air lock. As can be seen in the diagrams to the right the tunnels were constructed using two methods and although all the tunnels using the arched RSJ and corrugated sheeting have survived virtually intact the tunnels using the pit prop method have collapsed and are totally inaccessible.

Hugh looking at the collapse in the east passage
The west passage was blocked after approximately 60’ where the arched roof stopped, but it was possible to enter the latrines on the right hand side after a little digging. The east entrance being slightly higher up has a flight of 66 steps down and can be entered to a length of 120‘. This is also blocked by a collapse where the arched roof stops. Half way along this passage a similar set of latrines can be entered on the left hand side and opposite this can be seen the collapsed passage connecting to the west entrance passage.
It was hoped it would be possible to enter the engine room beyond the end collapse but due to the fact there was a 12’ void above the collapse and the passages are dug in Thanet sand, its was decided this would be too dangerous, so no further exploration was possible.

Chislehurst Cave Well

Guided tours of the Caves are available Click here for further details


Top of the well showing grill and winch tripod
22nd January 2012After many years of being dry, work started to clear out the debris thrown into the well.
As the well is inside the cave we weren’t able to use our petrol winch but fortunately power was available so we could use the electric one instead. 
Winching out the buckets

Coins removed from the well
During the day we managed to clear many buckets of chalk and soil thrown into the well along with several hundred coins thrown in over the years. After removing 5ft of spoil water is now visible and hopefully on the next visit we will be able to continue downwards and leave the well with water in the bottom.

Crossness Pumping Station, Kent

CrossnessHistory.The Crossness Pumping Station was built by Sir Joseph Bazalgette as part of Victorian London’s urgently needed main sewerage system. When the buildings were abandoned, the pumps and culverts below the Beam Engine House were filled with a weak sand and cement mix to reduce the risks from methane. We are helping the trust to remove some of this mix and explore some of the old tunnels.
More information on the Crossness Pumping Station can be found on their website http://www.crossness.org.uk
19th AugustWork started on helping, the group who are engaged in the restoration of the engines, in removing sand from one of the cylinders and a tunnel.looking along tunnel
lowering buckets14th OctoberWork continued on digging out the tunnel, until the daily influx of water, and on the area below the piston. Digging was halted around lunch time to enable us to hold our AGM in the canteen.
14th OctoberAfter lunch we concentrated on emptying the area inside the piston. 2 people inside the piston filling the buckets, 2 people man (and woman) handling them to the ground and then an electric winch to raise them to the surface, where we used wheelbarrows and a dumper truck to dispose of the spoil.Digging inside the pistonwinding up the buckets
Digging inside piston17th FebruaryWork continued inside digging in the area below the piston, The outlet valves can be clearly seen at the back and we are in the process of uncovering the inlet valves in the bottom of the chamber. It’s a good job that we have a fan to provide fresh air as it was getting a bit smelly at the bottom.
17th FebruaryOutside we are digging a hole which we hope will eventually lead through an arch and into the filth hoist chamber. Work is tough going even with a kango hammer as the infill here is much harder than inside.
Dumper17th FebruaryHaving a dumper truck to take away all the spoil is very useful, even if we have to barrow it out to it.
17th MarchWork continued on emptying the area below the piston and we had just finished this when a break through was made in the hole outside. Lunch was temporarily put on hold and a ladder found to investigate.Break through hole
Filth hoist bearingfilth hoist chamber17th MarchDescending down into the Filth Hoist Chamber we found that the infill had settled / washed away leaving ample room for us to enter and investigate. The photo on the left shows the Filth Hoist bearing whilst the photo on the right is looking out from the Filth Hoist chamber. The archway is under the main building foundations and the rusty metal on the left is the flywheel casing .
17th MarchSome of the digging crew.Digging Crew
14th AprilAlthough we expected to finish things off on the last visit we ran into some problems in our efforts to get to the base of the flywheel housing. As we lowered the level of the sand we opened up an easy route for the water in the outside access chamber to drain through into our workings. As a result we will have to shore up the excavation as we go.
14th AprilOn inspection we discovered that the area between the flywheel casing and the flywheel is full of debris and we are investigating the best way to gain access into the spaceIn wheel pit
26th MayDue to the confined space we were working in and the dust & fumes a fresh air supply was necessary. This home built blower and helmet was more than up to the task.Air supplyAir helmet
WinchLooking down pit26th MayOutside work started on emptying the pit. Unfortunately the spoil below the sand was a rather unpleasant black tarry sludge that stuck to everything.