Mount Snowdon

Mount Snowden was a mountain located in Wales. It was been used as a UNIT base in the 21st century. (SJA: Death of the Doctor)

While in Torchwood Tower, Yvonne Hartman referred to the base while talking with The Doctor. (DW: Army of Ghosts)

Sarah Jane, Clyde and Rani were taken to the UNIT base by Colonel Tia Karim to attend The Doctor's funeral held by The Shansheeth. Part of the base was destroyed when the The Memory Weave blows up. (SJA: Death of the Doctor)