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Frschengraben Bullinger. Der Frschengraben auf einem Stich von Johann Balthasar Bullinger Etwas links von der Mitte das Rennwegbollwerk und rechts der Kuttelturm Bullinger Zrich um upload March Johann Balthasar Bullinger upload by Adrian Michael PDold Johann Balthasar Bullinger Historical images of Frschengraben Zrich Rennwegtor