The actual entrance is to my left and back through a cute little courtyard. You stop in the small gift shop and pay your 4 Euro to wander through at your leisure. These steps lead to a door on the left that takes you inside the main part of the castle.
castle tours like this really give an American a feel for "true" historical buildings. I sat for hours on a brick wall in Worms staring at the Dome St. Peter imagining all the history that went with each brick.