One building with so many heating boilers. And this is just a small collection of their vents. It's part of the roof over the plumbers' practical training building.



Nikon F100 : f/8 : 1/400" : 300mm : ISO400

Lens: AF-S Nikkor 70-300mm f/4.5-5.6 VR
Film: Ilford Delta 400 (B&W)