Information about the 6km of the River Lez

River Lez location

The river Lez, a short and unpredictable Mediterranean torrent, was restored to navigation in the 1980s over a length of 5 km from the Canal du Rhône à Sète at PK 75.2 to the Port Ariane marina at Lattes, just south of the city of Montpellier.

Over the first two kilometres, the river winds between the lagoons and is lined by countless boats, many of them half abandoned and some even sunk. Then the river is enclosed between high flood embankments, with no possibilities for mooring, until the lock is reached. After Méjean bridge, the entrance to the marina is clearly marked, with a light showing red when the flood gate has to be closed.

This excursion from the Canal du Rhône à Sète is recommended for the excellent mooring in the marina, managed by Locaboat, with all services (except fuel) and for convenient access by tram to the centre of Montpellier.


River Lez regional mapHistoryWorks to make the Lez navigable inland to Montpellier were envisaged as early as the 12th century by the bishop of Maguelonne. Canalisation with three locks was planned by The Marquess François de Solas in 1666 and Royal assent was obtained in 1675. Works were completed in 1695. The waterway was extended to Palavas in 1719. It was acquired by the State in 1878, and closed in 1942. It was conceded to the commune of Lattes in 1980, allowing the restoration works to take place, and transfer of ownership is expected to take place in the near future.

Key Waterway Dimensions

  • Max Beam: 5.05m
  • Max Height: 3.30m
  • Max Draught: 1.50m

Local Waterway Links

For much of the short journey up from the Canal du Rhône à Sète the river is twisty, narrow and bounded by reeds and small home-made pontoons (for day boats). Keep to the centre, or the marked channel (there are buoys at places). From half-way along there are high embankments; benign and calm in summer, in the winter the river Lez can flood dramatically. Port Ariane has very large flood gates that are closed each night, even in summer.  Using a pilot-guide book is strongly recommended: Breil or Fluviacarte (Navicarte) guides.

There is one 17th century oval lock, monitored from the harbourmaster’s office at Lattes and operated automatically, although there is often a technician on site. Maximum authorised dimensions are 26.00m by 5.05m.

The Lez normally offers a minimum depth of 1.50m.

The maximum authorised air draught is 3.30m.

There is a rough path throughout most of the length on the left bank, set back from the river in the lower reaches, to bypass the fishermen’s huts.

Ville de Lattes, 1 avenue de Montpellier, 34970 Lattes

Click to enlarge

River Lez map

PK 0.0     Junction with Canal du Rhône à Sète  (PK 75.2) access to Paul Riquet boat harbour 300m d/s, 20 visitors’ berths, night €21, water, electricity, showers, slipway

See plan right for access south to the port de plaisance Paul Riquet. The first section of the route heading north is narrow, with many small boats tied to the bank or to ramshackle home-made pontoons (for day boats).

PK 0.4    Channel l/b to Étang de Méjean (small craft only)
PK 0.8    Short quay, 12m long, r/b

Carrefour supermarket with fuel immediately adjacent to the quay, designed to serve boats.

PK 1.4    Footbridge (Les Quatre Vents)

This is the lowest bridge (3.30m)

PK 1.7    Large boatyard ‘Les Quatre Vents’ for small craft, r/b, pontoon 60m long, private
PK 2.2    Mas des Salins huts l/b
PK 2.8    Camarguais restaurant and campsite r/b, pontoon

There are others on the Lez but they are often damaged by the winter floods. This one is between steel piles and can accommodate 2-3 boats. This stretch was once like a jungle in Vietnam, lined by tall bamboo, but has been completely cleared.



Approaching the lock on the river Lez
Approaching the lock on the river Lez (PK 4)

PK 4.4    Lock (Troisième Écluse)

A good pontoon and a good place to stay overnight if arriving too late. The lock is controlled via CCTV from Port Ariane’s capitainerie. There is an intercom on the control building by the lock (with alternative phone numbers if necessary). The lock is open from 8:00 to 12:15 and from 14:00 to 17:30, the same opening hours as the capitainerie at Port Ariane. The oval-shaped lock has vertically dangling chains to attach to.
From the lock proceed upstream and under the bridge, turn right past the capitainerie building into the port. Visitor pontoon (fingers of varying length) immediately to the right.

PK 5.3    Bridge (Méjean), D132
Lattes marina accessPK 5.5    Lattes marina (Port Ariane) entrance l/b, 6 berths for visitors, night €27-35, Locaboat hire base, water, electricity, showers, slipway, pump-out, shops, restaurants

Montpellier is very easily accessible by tram from the terminus of Line 3 at Lattes Centre. It is an easy walk down to the shopping centre in Lattes, which has a big market on Sunday mornings. Launderette and a small Carrefour.