Here is a little seen part of the Clifton Suspension Bridge:

We’ll let a spokesman from the Suspension Bridge Trust explain:

“If you’ve crossed the bridge recently, you’ve probably noticed that we’re having new covers put over the land saddles. Here’s a look at what’s down there!

“The weight of the bridge deck (or roadway) is carried by the suspension rods (which hang vertically) and chains (which run the length of bridge and disappear into the ground). The rods pull down on the chains causing them to sag and making them pull inwards at the ends.

“The downward force at each end is counteracted by the upwards resistance of the stone piers (or towers), but to prevent the chain from pulling inwards, it has to be anchored in solid rock at either end.

“At each end of the bridge, tunnels descend at a 45 degree angle into the rock of the gorge. At the end of each tunnel, the chains taper out in all directions and the gaps between filled in in with brick to form immovable plugs.

“Purely as a precaution, in 1925 and 1939 the anchorages were reinforced by extra chains and the tunnels back-filled to a six-metre (20-foot) depth with concrete.

“In this photo, you can see the steps which descend to a land anchor running alongside the bridge chains. Breathing apparatus is required to enter the tunnels – as is a love of spiders!”