Two contrasting open-cast coalmines in America use some of the largest machines of their kinds to be found anywhere.
At the Belle Ayr mine, Gillette, Wyoming, one of the world’s biggest electric shovels, the P&H 4100XPB, is removing overburden above the coal seams.
It dwarfs the Caterpillar 797B haul trucks it loads, even though these are the largest mechanically driven trucks in the world.

Among other impressive equipment is the world’s biggest motor grader available today, the Cat 24-H. Whereas Belle Ayr, one of the greatest mines in
the United States, uses a central electric supply for its shovels, the far smaller Beener Coal at Barton, Maryland, makes use of diesel technology.
Their Bucyrus-Erie 295B series II is the world’s biggest diesel-powered rope shovel. Working alongside it is another monster: the Komatsu D575A bulldozer – again,
the world’s largest.The programme focuses on extreme machines but also shows how these mines operate, from extraction and haulage to processing,
transport and reclamation. The script is by Keith Haddock, retired mining engineer and author of many books on earthmoving equipment.
For an extra he takes us to the Cam-Plex mining museum, near Gillette.