Old German cities are built around church squares. It makes sense when you think about it. When these cities were built, the Church (in most cases the Catholic Church), was the major authority. The church was the largest, tallest, most ornate building in town. It was a visual as well as spiritual focus.
When you wander around central Freiburg, the spire of the cathedral is seldom out of sight. As a side note, there is a rocking good gummi bear store just next to the guy holding the umbrella. Rum and coke gummies for the win!