Chemin de fer de Petite Ceinture

The 32-kilometer (20-mile) ring route circles central Paris through various neighborhoods, running along tunnels, viaducts, and ground-level tracks. Multiple former stations dot the line, their 19th-century architecture still visible beneath layers of vegetation. Some segments have been converted into green corridors, while others remain fenced off or continue serving freight operations.

Construction started in 1852 under Napoleon III to connect the city's major terminal stations. The complete passenger loop opened in 1869 and carried up to 39 million riders annually by 1900. Passenger service ended in 1934 as the underground Metro system rendered it obsolete, though freight operations continued on certain sections until recent decades.

Before the Metro network expanded, this route served as a vital connection between major rail terminals and surrounding districts. Daily commuters relied on the service to traverse the city efficiently, avoiding congested streets below. Following its closure to passengers, the abandoned infrastructure became a canvas for street artists and a symbol of urban transformation in contemporary Paris.

Several sections of the former track are now accessible as public pathways for walking or cycling through different districts. Access points exist in the 12th, 15th, 16th, and 18th arrondissements, with some portions open seasonally or during scheduled times. Other segments remain closed to the public or continue serving freight trains.

The infrastructure includes 12 tunnels and 24 bridges, with abandoned stations gradually overtaken by wild vegetation since closure. In the 1990s, portions served as filming locations for French cinema. The former Auteuil station now houses a restaurant, while other station buildings have been converted into private residences or artist studios.