St Petri (St Peter's) was built between the twelfth and the fifteenth centuries and badly damaged in 1942. The interior was rebuilt as a deliberately empty hall — there is no fixed altar or pews — and now functions as an exhibition and event space, not a working parish church. The whitewashed walls and clean Gothic ribs are striking precisely because nothing else competes.
The reason most visitors come is the lift. The 50-metre tower has an open viewing platform at the top, reached from the south transept, and the view over the Altstadt's red roofs, brick spires, and silver Trave channels is the best in the city. A small charge gets you in; the lift saves the spiral stairs.