Promising start but then many busy roads. Closed nature reserves, wetlands, oil refineries, good variety.
Today there were direct trains both ways but there was a cold 2.5 hour wait at Rognac for the return train, unuaually requiring shelter in the waiting room.
This walk was the most interesting but perhaps the least nice of the week. There were Roman remains, low hills with rocks, nature reserves you could not get into, wetlands and oil refineries. There were good picnic places in unlikely positions such as a dual carriage way roundabout. Hidden behind a bush with a view over the Étang de Berre and out of sight of the traffic, it was completely private. No pedestrian in their right mind would come here!
The middle of the walk was through wetlands. Then the industry started. There was only one feasible route into Rognac and it was a busy road with sections of dual carriage way. There was a cycle path so walking was fairly safe until the flyover junction where the cycle facilities vanished. Luckily it was fairly quiet on this winter Saturday. A hypnotic flame of eternal youth was burning at the refinery.
The wind had dropped but it was overcast and misty. Just like England but warmer. This also was fortunate because a long wait for a train in cold wind is not pleasant.
This was the last day of flat terrain. Rocky hills could be seen looming over Rognac with limestone cliffs, steps and ridges. Planning the routes will need more care and avoiding the traffic will be harder.