View of the Grand Canal d'Alsace Lock

If you cross the Rhine, which forms the border, you will reach this lock in France for shipping in the parallel Rhine side canal (Grand Canal d'Alsace). To the west of the lock there is still a hydroelectric power plant and a little south on the canal is the recently decommissioned Fessenheim nuclear power plant. If you ride your bike south in the direction of the photo in front of the bridge over the lock on the island, you will have a few kilometers of coarse gravel in front of you. Although the path is wide and flat, it is quite difficult to ride a touring bike or gravel bike, especially in strong headwinds. The path actually requires wide mountain bike tires, even though it is perfectly flat. Only after a few kilometers do you reach the edge of a golf course along an almost overgrown path and a very beautiful road through the forest with new asphalt that leads to the Rhine bridge in Neuchâtel.
Under no circumstances should you try to cool off in the water of the canal because it is surrounded by dangerously slippery and steep concrete. The enclosure has no stairs anywhere and it seems almost impossible to get back to land from the water.

Switching to France at the Fessenheim power plant is only worthwhile if you don't want to cycle directly along the canal (the "cycle path" is rocky and bad). Bad signage! If you want to venture further inland, okay...

Here you can watch Rhine cargo ships passing the lock.