Airfield names
Long after Croydon closed (1959) the rotating beam was kept going for a considerable time.
Also Banstead railway staion (to the west ) had its name boldly emblazoned for many years and apparently was a reporting point in the early radio days.
I have seen large white crosses marked in unusual places but some of them were 'range indicators' to ensure correct direction of aircraf for firing/dropping.
In the case of a marker for BH then Croydon would be in the same direction or very close.