Sentier du Blongios: the marsh outing
Start at the La Grange Nature car park, 18 rue du Romelaëre, Clairmarais. The departmental route card gives a 4.3 km out-and-back with 9 m of ascent, including the approach from this starting point; it describes 2.8 km through the reserve. Follow the signed public route to the bird observatory and retrace the permitted route to the same car park. Allow 1½–2½ hours with stops, rather than treating the card’s one-hour walking estimate as a wildlife-visit target. Pause where the path widens, watch open water first, then scan the reed edge. You can turn back earlier if the full outing is too much for your group.
The route card identifies wooden decking and wheelchair/pushchair access. Confirm the condition of the complete approach and boardwalk with La Grange Nature; wet wood can be slippery. Do not assume a separate return path or another nearby circuit has the same accessibility.








