Not as much as there was 40 years ago sadly. A section of full depth double track cutting, a few sleeper blocks if you know where to look (used in a garden gateway, not in situ), the weighbridge cottage at Merstham, the Dean Lane Bridge, the embankment in Coulsdon, a few vague earthworks traces between Coulsdon and Croydon, and a bit of reconstructed track (2 plates) in a park in Purley. The two main Brighton lines and the M23 have destroyed most of what ran south of Coulsdon, although this is where much of what liitle survives can still be found.