Hidden Victorian reservoir revealed in Nottingham

The BBC has been given a rare glimpse inside a Victorian reservoir that has been hidden from public view for more than 160 years.

Belle Vue reservoir, which lies under a mound in Mapperley, Nottingham, was built by Thomas Hawksley in 1851.

The underground complex, which has been drained for maintenance by Severn Trent Water, serves about 150,000 people.