They aren't allowed to turn back uphill. They can't turn tail. They are forced on this perilous journey. Did you know the canal aren't allowed to return home? Yep. They just start pouring in, and then they're off. Not allowed to retreat. They just keep on going, for as long as they can. They carry their ships on there too. In fact, the canal have no language. They are completely mute. In fact, shown in the image below is a canal ship, it's name unknown. If was spotted in bath-Hampton earlier today. Shown is a canal base of operations: https://upload.wikimedia.org/wikipedia/commons/9/98/Canal.at.bathampton.arp.jpg