Visitors are now able to stroll through the now-defunct Leicester-Swannington Railway tunnel and discover the history behind the historic structure.
The Glenfield Tunnel, built in the early 1800s, runs for a mile beneath Leicester's streets and has been closed since 1966.
David Lyne, from the Leicester Industrial Historical Society gave the group a guided tour of the tunnel, explaining its history and the project which has brought it back to life.
Leicester City Council bought it for just £5, and spent £500,000 restoring its crumbling walls to meet safety standards.
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A sunny but chilly start. Cloud increasing with a little rain affecting northern and western areas, especially over the Derbyshire hills.
After a mainly dry, and locally chilly start, cloud will thicken, with some patchy rain possible across northern counties.
Becoming generally dry overnight with clear spells. A sunny but chilly start tomorrow. Cloud increasing with a little rain for some.