Brunnchen' date=' Wipperman, Hohe Acht, Steilstreke and the Karussell[/url'] is the answer as they are all on the same walk route and you never leave track side. And there is ice cream when you get back to the car park.
I'm not too worried. The tunnel trains just use loops at each end and it's all pretty computerside And in fact it's probably capable of being controlled completely by one end or the other. And I suspect the tunnel and track is owned and run by eurotunnel rather than network rail.