The jalle du Nord or L'Horte is a channeled stream that crosses the old marshes of Beychevelle (or Sainte-Gème or Saint-Martin). It is one of the elements that allow the drainage of marshy lands, with the Middle Channel and the Midi Channel which run parallel to it. It cuts the road from Bordeaux to Pauillac at the so-called Beychevelle bridge, equipped with a valve; nearby, another bridge crosses it before it continues on its way along the park of Château Beychevelle.
It joins the estuary at the port of Beychevelle. A flood gate has been fitted there.