The Box Tunnel – Brunel builds the impossible

The Box Tunnel – Brunel builds the impossible

Published 8 April 2021 | Average read time
2 min read
Stories From the archive Industry-leading

The Box Tunnel in Wiltshire is one of our finest Victorian structures. It’s also one of the railway’s greatest triumphs.

Once completed, it inspired short stories and poems, cementing itself in the minds of the Victorian public as a marvel of the age.

Yet there would come backlash. It was labelled as ruinously extravagant. The media publicised its virtues but also reported on the fears of the public, who were terrified about travelling through the subterranean darkness.

There was also a large human cost to its ambitious construction, with more than 100 deaths occurring during the project.

Inside, the site smelt of smoke and gunpowder. The dark and dim vault filled with clouds of vapour and only feeble candlelight saved it from utter blackness.

Original drawing of Brunel's Box Tunnel from the Network Rail archive
Original drawing of the Box Tunnel, owned by the Network Rail archive

Its designer, Isambard Kingdom Brunel, achieved the impossible at Box despite the harsh working conditions, tragic deaths and controversy.

With it, he pushed the boundaries of engineering and created one of the world’s most iconic examples of tunnel design.

Black and white photograph of Isambard Kingdom Brunel with top hat and cigar
Isambard Kingdom Brunel

Box Tunnel in numbers

  • One tonne of candles needed each week so the workers could see inside the tunnel
  • One tonne of explosives a week to blast through the earth
  • Less than two inches – the difference of alignment when the two ends of the tunnel from the east and west sides of Box Hill met in the middle
  • 4,000 – the number of men needed to finish its construction after the project missed its deadline
  • More than 100 – deaths during the project
  • 300ft – the depth of the deepest shafts dug inside the tunnel (about 100ft taller than York Minster)
  • More than 20 million – the bricks it took to build

Video: the Box Tunnel in Wiltshire

Click below for the extraordinary history of the Box Tunnel

Read more:

Our history

The Network Rail archive

Eminent engineers

Iconic infrastructure

What’s a Main Line? Rail history explained

Incredible Stephenson railway history rediscovered

Read the George Stephenson notebook online

People and the railway: the Railway Heritage Trust