Coming from Munich, Innsbruck or Vienna take A10 to Villach and leave the Autobahn at Exit Salzburg Süd(south), after you pass VW at the INFORMATION  Salzburg "Park & Ride"(P&R) go right (green sighn AIGEN) over the Hellbrunner bridge, after bridge in the circle go left to Salzburg Zentrum, in front of you your will see a train underpass, right before the underpass go in to the right and follow the signs to Hotel Doktorwirt.