In Paris, an old bus line on the Maréchaux Boulevards has been replaced by a modern tramway. Simultaneously, the road-space has been narrowed by about a third. A survey of 1000 users of the tramway shows that the tramway hardly generated any shift from private cars towards public transit mode....

The paper argues that congestion in public transportation is alike the much more studied road congestion. It sets out to produce, on the case of the Paris subway, a congestion cost curve linking the willingness to pay for non-congested travel to actual congestion levels. Congestion costs appear...