Though relatively new (to people like me, at least), relatively few of these early 1960s flat-top blocks survive on Gainsborough's Uphill Estates. This is "Pilham Court", built around 1964 to house people dispaced from the old Town during the slum clearances in the Bridge Street area.
This is actually the back of Pilham Court, the front of which looks like this.
Camera: Nikon F5
Lens: Nikkor 35-70mm zoom
Film: Kodak Ektar 100