When you stay where camera is and simply whatching through the tunnel, how far kann you actually watch?<br>I just see light on the end of the tunnel, literally, and i ask how far is this really? 500m, 5km or may 50km. :O<br>It looks really far away.,(reply>), @***** Ah ok thanks. :D,(reply>), +TheJetiLP Maybe 1km or so? Cable tunnels can twist and turn more than train tunnels (but not much more!), so they fit around what's already under London!