The source of the River Beck is in Spring Park (grid reference TQ377647) where Shirley and West Wickham meet.
For its first mile or so it forms the border between the London boroughs of Croydon and Bromley.
The Beck flows into Cator Park, where it is joined by the Chaffinch Brook.
[1] The name probably derives from the town of Beckenham – Beohha's homestead (Old English).
[2] An alternative derivation may be the Middle English beck (stream), which would be an example of a tautological name.