However, I am trying to work out what it is; with apparent walkways between what look like railway tracks, over pits, but with no 'between the rails' discharge holes, then there are the chimneys/vents too - most odd.
and as Kit says, disused for a year or two I'd say.
Fascinating, it holds the attention, well mine anyway,
It is a shutdown blast furnace. It was closed in 1985 and converted into a park. Blast furnace no5 is a lookout point today. From there I took that photo. The holes beside the rails are ore and coal bins. I added two photos for better explanation.
Picture taken from there
Overview
If your are interessted in more details just take a look here.