Just spent an excellent day there. If you're in the area it's well worth a good few hours there.
They have lots of interesting machinery including a child-powered treadmill copied from Agricola.
Their 'underground' mine tour is one of the best I've seen. It's a cut and cover thing but really does give a good idea of a modern mine.
There's also a fantastic exhibition on explosives and another on mine rescue. For the real anorak there's the biggest collection of personal lamps I've ever seen.
A smattering of Spanish might help but you can get by without it. Quite a few machines from Britain there before the Belgians and the Germans took over building machinery for them.
In my opinion it's not as good as the Big Pit but better than anything else over here.
Obviously the whole area is in uproar at the moment with many of the working mines shut down due to industrial action. Almost everyone seems to be wearing a small black ribbon to show solidarity with the miners.
It's a bit tricky to find as the signage peters out at a crucial moment but it's pretty obvious.
The finest workers in stone are not copper or steel tools, but the gentle touches of air and water working at their leisure with a liberal allowance of time.
Henry David Thoreau