What's it like inside the four-mile-long Severn Tunnel?
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Inside the closed four-mile-long underwater Severn Tunnel

The Severn Tunnel has been closed for six weeks to upgrade the infrastructure ready for electric trains.

Shutting the south Wales to England rail link has added an extra 40 minutes to journeys to London and the south west.

But as London trains are diverted via Gloucester, there is a rare chance to go inside this feat of Victorian engineering.

  • 22 Sep 2016