This is Surrey Street Market which has existed in Croydon since 1276. The light installation under the footbridge is by Lauren Baker, and says "a simple hello could lead to a million things". Best viewed on black.
I just love night-time photos. I like the coloured lights strung across the road. BTW in answer to Octogenarian - the buildings each side look a lot newer than the 13th C. Maybe rebuilt after the war?