This awful mess was the main outlet valve of the water tower soon after we bought it. Siezed up solid, it is surrounded by rubbish and there seems to have been a black paint incident.
As part of the painting of the atrium I decided to have a go at getting the valve back to working order.
Much use of WD 40 and crow bars and it is now back in business, good as new.
The pipe nowadays carries rainwater from the roof to our rainwater harvesting tank.