Large water tank (Kington) (Newton HR5)

I think it is a water tank, perhaps for livestock? It is substantial and rigid.
Dimensions: 3ft x 2ft x 2ft deep. There is an inlet/overflow hole just below the lip.
It might make a good base for a garden pond, if not put to its original use.
As you can see from the photos, it will need a good clean before use.