Joseph Williamson

Joseph Williamson was a philanthropist in early-19th century Liverpool.

In 1820, he funded and supervised the digging of tunnels whose purpose was unclear to his contemporaries, although they did provide employment to the poor. He seemed to have some inkling of a great upcoming cataclysm which would somehow justify the tunnels, although he only spoke of it cryptically and evasively.

In the 21st century, these tunnels were called Williamson Tunnels in his name. (TV: The Halloween Apocalypse)

He found himself on the planet Time, where he briefly met Yasmin Khan. (TV: War of the Sontarans)

Behind the scenes
In the real world, the tunnels' true purpose is unclear, and is the subject of much academic speculation.