Prairies Saint-Martin, Public park in northern Rennes, France

Prairies Saint-Martin is a large park north of the city center with meadows stretching between the Ille-et-Rance canal and a natural river course. The grounds feature walking paths, children's play areas, and grazing zones where Highland cattle naturally maintain the wet grasslands.

The first recorded structure was the Trublet water mill, documented in 1625. In 1895 Laurent Zwingelstein bought the mill and set up tanneries there, which produced up to 70,000 hides a year by 1925 and closed in 1948. In 1929 the Office départemental des Habitations Bon Marché laid out workers' allotment gardens. The city redeveloped the flood-prone, polluted meadows into a nature park between 2014 and 2021.

The name comes from the Saint-Martin district; the meadows were long worked as allotment gardens. From 1929 the Office départemental des Habitations Bon Marché laid out workers' plots here for Rennes labourers living in flats without a private garden. Some garden sheds were gradually converted into homes, and residents still cultivate the family plots beside the Ille.

The park lies north of the city center, between the Ille-et-Rance canal to the west and a branch of the Ille to the east, with a flat relief and no motor vehicles. Entrances line the canal and rue de la Motte Brûlon, and footbridges installed in 2020 link the surrounding new districts. Bus lines 12 and 32, the Jules Ferry metro station and self-service bike stations at Auberge de Jeunesse and Armorique serve the site; walkers and cyclists share the through routes.

The site's industrial past left soil pollution in the family gardens, detected in studies between 2008 and 2010; the cause was never fully established, though the former tanneries downstream at Trublet are the likely source. Not every plot was affected.