Dark Matter: The underground lab unlocking the Universe
Tucked away in the North East of England is ICL Boulby Mine, a working polyhalite and salt mine and the second deepest in Europe.
Over 1km below the surface, in a small corner of the giant mine's network of tunnels is a unique laboratory that could hold the answer to one of the biggest mysteries of the Universe - dark matter.
Video by Adam Proctor
Scritped and presented by Lee Johnson