How Deep Is The Severn Tunnel?
The brickwork is between 27.0 inches (686 mm) and 36.0 inches (914 mm) thick. Around the deepest part of the tunnel, the roof is only a maximum of 50 feet (15.2 m) beneath the river bed. How many people died building the Severn Tunnel? A memorial plaque to commemorate four men who lost their lives …