The Burham Tunnel was used to take chalk from a quarry down to the river.
Today the quarry is abandoned and the tunnel is derelict.
There are 2 obstructions in the middle tunnel which are difficult to pass. One is a wall (and I have no idea why someone would build a wall in the middle of a tunnel), and the other is where the tunnel has collapsed.
Also some healf and safty nutter has blocked up one of the tunnl's entrances, the other entrance (the one in the quarry) is also blocked, but is just about passable.
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