I toured on my own today. There is a nice waterfront that runs a few streets from the main area. And I found four sets of these steps to get to the Dom plaza.
St. Stephan's interior.
The market filled the "domplatz". (Plaza in front of the church)
Later in the afternoon the sun peeked through the clouds and lit the homes along the river to create a nice reflection.
Passau calls itself the town of "Three Rivers". The Ilz ( I L Z) and Inn join the Danube. The Inn is a lighter color than the Danube. Here is where they join. I squinted to see the difference. Maybe it is easier to see on a sunny day.