Jardin écologique de Lille, Protected nature reserve in Vieux-Lille, France.

The Jardin écologique de Lille is a nature reserve in the historic quarter with woodland areas, shrubland, a pond, and the Tortue River running through land once enclosed by Vauban fortifications. The space contains diverse habitats including native vegetation and water features that have adapted to the historic fortified landscape.

In 1985 residents of the old quarter took over this abandoned land within Vauban fortifications and formed an association to manage it. This site became France's first ecological garden, demonstrating how unused urban spaces could be restored and returned to nature.

This space serves as a meeting point where local residents and visitors discover how nature thrives in the heart of the city, with native plants and creatures coexisting in their natural settings. The volunteer guides share knowledge about the woodland and wetland ecosystems that define the region.

The entrance is at the end of Rue du Guet, on the Plaine de la Poterne in Vieux-Lille; the site is a fenced, wooded enclosure of 2.5 hectares. Volunteers of the association Lisière(s) open the gate on Sunday afternoons. The garden lies along the canal de la Tortue and the hornwork of Saint-André, between Lille and Saint-André-lez-Lille.

The Tortue was not named after a battle: it earned the nickname "la rivière à morts" after the 1708 siege of Lille, when 18,000 Austrian soldiers died. Its water was stored in the Grand Carré of the Citadel to flood the city's northern front against attack. In 1975 a wide-gauge canal cut its course, and it now runs underground through a siphon beneath the Moyenne Deûle.