We asked road safety partnership GoSafe and Welsh police forces how many motorists were caught at 20mph monitoring points across Wales.
The map above shows the results from 97 enforcement locations, in the months from January to October and we got details of nearly 62,500 offences.
At Gellideg, 1,000 drivers were caught in October alone.
This section of the Swansea Road is among 20 being looked at by Merthyr Tydfil council and which could eventually be switched back to 30mph, subject to consultation.
Other hotspots include Gors Avenue in Townhill, Swansea (3,700 offences), while five other stretches of roads in Flintshire are in the top 10.
Dyfed-Powys Police was unable to extract the data for us concerning about 1,900 offences at 88 points and we are awaiting a response from Gwent Police regarding 74 monitoring sites in its area.