Williamson Tunnels
From Tardis Wiki, the free Doctor Who reference
The Museum of Liverpool contained an exhibit on the Williamson Tunnels on 31 October 2021.
Joseph Williamson was working on a series of tunnels beneath Liverpool in 1820. James Stonehouse argued that they were without purpose, though Williamson argued that he was preparing for "the cataclysmic". (TV: The Halloween Apocalypse)
Behind the scenes
In the real world, the tunnels' true purpose is unclear, and is the subject of much academic speculation.[1]