The best traffic-free bike rides in Réserve Naturelle De Roque-Haute

very inconspicuous and a bit little water pressure, but it will run in June 2026

It is difficult to imagine that waterways cross here like at a crossroads. Built in 1676 by engineer Pierre-Paul Riquet, the round lock of Agde is unique on the Canal du Midi: its circular shape and its three gates allow boats to choose between three different directions. Depending on their course, they head back towards Béziers, towards Agde, or towards the Étang de Thau. An ingenious river junction at the entrance to the town.

Good viewpoint to look over the entire nature reserve.

The Saint Roch footbridge, inaugurated in 2016 in Sérignan, is the first structure to cross the Orb river since the construction of the old metal bridge at the very beginning of the 20th century. It was, moreover, the only access road to the village and the beaches. But the width of the roadway and the sidewalks made circulation dangerous for cyclists and pedestrians. The footbridge, 80 m long and 3.50 m wide, is on the contrary reserved for them, as well as for people with reduced mobility. Crossing the Orb via the Saint Roch footbridge, lingering to watch the currents rush downstream, enjoying the view of Sérignan and the collegiate church, the wild banks of the Orb, constitutes another way of entering Sérignan.

The single lock of Portiragnes opens onto the Agde reach downstream. This is a typical area of the landscapes of the Languedoc coastal strip. Indeed, from this lock onwards, the canal surface is at an altitude of only 1 meter above sea level. It runs alongside wetlands of former salt ponds (la grande Maïre), where a rich fauna and flora are found (bulls, horses, waders, amphibians, reeds...) and some pine groves. These places are conducive to the establishment of numerous campsites.

The single lock of Portiragnes opens onto the Agde reach downstream. It is a typical area of the landscapes of the Languedoc coastal strip. Indeed, from this lock, the surface of the canal is at an altitude of only 1 meter above sea level. It runs alongside wetlands of former salt ponds (la grande Maïre), where we find rich fauna and flora (bulls, horses, waders, amphibians, reeds...) and some pine groves. These places are conducive to the establishment of numerous campsites.

The round lock of Agde is the most original on the canal. Built in 1675-1676. It was put into operation in 1678 when the canal from Béziers to the Étang de Thau was opened to navigation. A particular situation, an original response: it was decided to build a round lock with three gates. The first opens towards the city of Sète and the Étang de Thau via a short passage on the Hérault; the second opens onto the canal coming from Béziers; the third opens onto the small canal which allows small boats to reach the city of Agde and its maritime port and then Grau d'Agde. The round lock was commissioned in 1678 when navigation opened between the Étang de Thau and Béziers. It originally measured 30 meters in diameter with a depth of 5.20 meters in the center. Thanks to this round lock and the low canal, small maritime boats can come onto the canal!

An ideal footbridge for crossing the Orb by bike or on foot. Much more pleasant than the busy road bridge.