Subterranean
bridges might conjure images of Khazad-dûm in the Mines of Moria, where
Gandalf faces the Balrog in The Lord of the Rings. Here on
middle-of-the-road Earth, however, things are not quite so dramatic.
Not quite, but nearly. In the bowels of underground abandoned mines,
bridges of timber supported by rusting metal chains cross precipitous,
abyssal gaps; yet mine explorers need no second invitation to brave
them.

View from up top: Moel Fferna’s Bridge of Death

The rotten planks of the legendary Bridge of Death in the Moel Fferna
slate mine, North Wales straddle a heart-stopping drop, but this bridge
is actually in better condition than most found in the Welsh slate
mines. Even so, treading across to make it to the other side will earn
you some well deserved kudos with the mine exploring community.


Subterranean Bridge of Death: Moel Fferna slate mine

This image shows another perspective on Moel Fferna’s impressive Bridge
of Death, which spans the roof of a large, high vaulted chamber. A
scarcely visible tramline runs along the chamber floor, where the
silhouette of a mine explorer can be seen. Moel Fferna is a rare case
of a slate mine where there is no trace of surface workings; they were
all completely underground.


Rotten Bridge beneath the surface: Bleanau slate mine

Emerging from the claustrophobic confines of a derelict mining tunnel
only to find yourself faced with a bridge that looks as though it might
collapse at any moment is not an experience for the fainthearted. This
next bridge is not even safe to set foot on, so decayed is it by the
clawing hand of time: climbing ropes fixed to the rock face on one side
were needed to traverse the uncertain gap it spans.


Into the unknown: A mine explorer clings to the wall while darkness looms ahead

The exact location of these next few bridges must remain unspecified
because they were photographed before gaining access to the tunnel
network in which they lie became an issue. Suffice to say that at their
peak in the 19th century, the combined quarries produced well in excess
of 50,000 tonnes of slate each year and together represented one of
Britain’s biggest.


Rickety crossing: Another bridge in a mine system that must remain nameless

In fact, in its heyday north-west Wales was home to the largest slate
mines and quarries in the world, and the slate industry dominated the
economy of the region until decline set in at the beginning of the 20th
century. The Great Depression sandwiched by two World Wars saw the
closure of many smaller quarries, while competition from other roofing
materials led to the larger ones being shut down in the 1960s and ’70s.


Underground Bridge of Death: Croesor Quarry slate mine

Croesor is another Welsh slate quarry that lies almost entirely
underground. Despite a series of collapses, it is possible to make the
trip from Croesor to the nearby Rhosydd Quarry via a tunnel. Home-made
bridges, fixed ropes, zip wires and even inflatable boats have been
installed to make this classic mine explorers’ trip possible, if not
necessarily safe. These pictures show the final and most awkward
crossing – another ‘Bridge of Death’.


Making the crossing: Ropes help explorers over Croesor’s timber bridge

Why are these bridges such a feature of Wales’ long disused slate
mines? Well, where the slate was worked away below the main haulage
floor, building a wooden bridge across the hollowed out chamber
maintained it as a through way. Often suspended from chains fixed into
the roof above, these bridges could be as much as 100ft (30m) above the
floor below; high enough to let giddiness set in after a brutal day’s
work at the rock face.


Chamber of Horrors: Remains of bridge across a double chamber in Croesor

The image above is another stage in the Croesor-Rhosydd through trip,
affectionately dubbed The Chamber of Horrors. As photographer Simon
Lowe told EG: “This bridge was unusual in that it spanned a double
chamber and as the photo shows would have rested on the quarried away
wall”. The bridge supports still exist, doing a bad impression of a
trapeze, while the partially worked away wall separating the chambers
can be seen on the right.


Floating bridge: Beams of a bridge over freezing water in Croesor

The water in these underground cavities may look inviting, but be
deceived ye not: it’s deathly cold. Mine explorers must not only
wrestle with claustrophobia and vertigo; when negotiating bridges that
don’t teeter over dizzying drops, the prospect of water at temperatures
that could quickly bring on hypothermia may await. Above, the metal
beams of a bridge over a flooded chamber in Croesor beckon the
sure-footed. We’ll leave it to the mine explorers and Gandalfs of this
world.