I have been following Martin Zero's Youtube Channel for over a year now, and recently he visited 2 former colliery sites in Lancashire.
Both are unusual in that he managed to get a look into 2 still open shafts, using a homemade camera vehicle.
Previously, he has made a 3-part video series on Wet Earth Colliery, where he explored the remains of James Brindley's siphon beneath the River Irwell, and the now abandoned Jubilee Colliery near Rochdale.
Alderley Edge copper mines have also been the subject of his videos.
I attach links to his 2 most recent mining videos, covering the Great Haigh Sough and the Aspull Pumping Shaft (the view down into this through a small hatch in the ground is spectacular) and the Tunshill Colliery above Rochdale, where he lowers a camera down a spectacular masonry lined shaft.