Between Burghausen and Simbach am Inn, there is a 14 kilometer, two-lane section that is signed as Bundesstraße 12.

This path would have decreased travel time from Munich to Vienna compared to the route via Salzburg.

However, since Austria did not want to burden the Innviertel with traffic, the plan was given up on the Austrian side.

This makes an eventual northern extension to the Czech border possible.

At one point, a route from Mühldorf to Pfarrkirchen to Pocking was planned.