[2] However, research by staff and volunteers of the Williamson Tunnels Heritage Centre has shown that he was born in the West Riding of Yorkshire and that his father was a glassmaker in a small village near Barnsley.

[4] Following this, he continued to employ his workmen, and recruited more, to perform tasks, some of which appeared to be useless, such as moving materials from one place to another and then back again.

[5] Williamson retired from his business in 1818 but continued to be a landlord, one of his tenants being the Unitarian philosopher, James Martineau.

In the 1830s he came into contact with George Stephenson who was building the extension of the Liverpool and Manchester Railway from Edge Hill to Lime Street stations and whose own excavations passed through those of Williamson.

Williamson died in 1840 aged 71 at his home in Mason Street, the cause of death being "water on the chest" (an archaic phrase later known as dropsy).

[9] On one occasion he invited guests for dinner but served them only a simple meal of porridge and hard biscuits.

[11] On one occasion Williamson set free all the birds in his wife's aviary, declaring that it was a pity that men did not also have wings to enable them to enjoy liberty.

Williamson's tunnels provide the key which helps the Thirteenth Doctor (Jodie Whittaker) save Earth from trans-dimensional invaders.