I worked as a photographer for the old West Glamorgan County Council between 1974 and 1980.
Every day as I drove along Fabian Way in Swansea,I would see this possible picture. Usually the light was wrong or there was no light.
One morning I reached this spot. The rails were lit by the sun and I rushed to take the picture. Shortly afterwards the good light was gone. This picture was taken about 1976.