In 1970, 35 ramps on the Paris freeway network were equipped with traffic lights running on fixed time cycles that were set for morning peak periods during the week, and for the week-end returning periods (Kunkel, 1999)[8]
There is some evidence that there are 100 ramp meters in the UK
The successful results obtained since then lead to a steady increase in the metered sites to reach approximately 20 sites in 2000