La Petite Ceinture

A panoramic composite view of the 15th arrondissement from the Petite ceinture.

La Petite ceinture ('little belt') is an abandoned railway line that runs for about 30km around Paris. Until recently it has mostly been out of bounds. The railway company still owns the land and there has been a lengthy argument about what to do with this serendipitous brownfield space. Most people want it in public ownership and repurposed for leisure activities. Up in the 18th arrondissement the local residents took matters into their own hands a few years after the railway closed and have created some much loved community spaces and facilities. However, despite spending time in the area, we've never visited this section of the Petite ceinture (kicking ourselves now, to be honest...)

One of the many info boards along the track.

So when we went to Paris in early February one of the attractions of the apartment we rented in the 15th was that it overlooked the 1.5km section of the Petite ceinture in this arrondissement. This part has been developed by the local authority to form a walking path and long skinny nature reserve. Left for 25 years to become overgrown it became a wildlife haven, a corridor for foxes, hedgehogs, birds and bumble bees.

The new path, incorporating the old rails.

The section through the 15th is the most gentrified. It's used by joggers and dog walkers primarily. It has lifts from street level up to the old track bed at regular intervals, benches made from 'sleepers', and decking 'platforms'. A generous path was formed by packing the track with hoggin so that there was a level walking track but the rails are still visible, integrated into the path.

The lift in front of our apartment, taken from the apartment window.

All along the track are information boards describing the wildlife you might encounter at that spot. One of the most impressive is a tall dead tree, sprouting honey fungus out the top, nicknamed la Chandelle ('the candle'). The info board explains the tree has been left there for large wood boring beetles.

The entrance to one end of the section of the Petite ceinture that runs through the 15th.

The information board at the beginning of the section says:

Constructed around Paris under the Second Empire (1852 - 1869) this railway line transported passengers up to 1934 and goods up to the end of the 70s. In the 15th arrondissement, it particularly served the Citroën factory and the abbatoirs of Vaugirard. Since then the vegetation has spontaneously appeared on the banks, ballast, bridges and walls, forming different strata where numerous animal species can live.

To allow public access to the site the City of Paris has landscaped it whilst preserving the railway heritage and improved the unique biodiversity. The trail is reversible in case of occasional rail usage.

The Petite ceinture in the 15th brings together varied and interesting natural habitats in Paris such as woodland, grassland, wasteland, woodland edge and vegetation colonising the ballast and walls. Each of these environments harbours different animal species. Two hundred and twenty species of plants and animals live here or use it as an ecological corridor between the Parc André Citroën and the Parc Georges Brassens.

Along the wooded slopes 21 species of birds nest, amongst them the threatened Spotted Flycatcher Muscicarpa striata (Fr.  Gobe-mouche gris). In the more open areas like the woodland edges, the grassland and the ballast, bees, wasps, butterflies and beetles come to nectar.

This walking trail was developed so that the public could use it whilst respecting the existing natural heritage. The habitats have been preserved and elements of the railway heritage have been conserved and reused. Finally, in order not to disrupt the lives of the wildlife, no lights have been installed, and the site is closed at night. The banks are not accessible.

Maintenance is timed so that it does not disturb wildlife, particularly nesting birds. The idea is to maintain three stages of vegetation, and the grassland is mown once or twice a year. Woodland clearings are created to encourage the growth of local trees and shrubs, such as Field Elm, which is becoming rare, or English Oak and Sycamore. The trunks of dead trees and piles of wood are left as habitat for micro-organisms, fungi and wood boring insects. These all work to decompose dead wood and are essential for maintaining the ecological balance in a forest ecosystem.