Navibus is the name given to a water transport service offered in Nantes. The small boats cover three lines in the Loire and Erdre rivers and carry passengers along across the river. Each line has different boats, but all accept passengers (4 in the smallest, 10 in the largest). They are owned by the same company as the tram and the stops are near tram or bus stops. The "Navibus Loire" connects Rezé and Nantes in a short 10-minute trip. The "Navibus Erdre" has 6 stops and travels along the Erdre, a tributary of the Loire. Finally there is the Navibus "Passeur de l'Erdre" which runs between Port Boyer and the university campus.