Cars on Trains
Allow routes to use services where the car is loaded onto a train (bit like a land ferry), e.g Auto Train in the USA, Eurotunnel in UK, and others in Europe, Australia. The route should be "schedule & wait time" aware
Also when you choose such a route, allow entry of a booked time to influence the route and notify of departures/wait times when getting close to the departure point.
All of this would be similar to a ferry although cars on train routes tend to be more "optional", and may not be quicker.