St. Stephen's Cathedral's massive south tower, the dominant feature of the Vienna skyline at 136 meters (445 feet).
It served as the main observation and command post for the defense of the walled city during the Siege of Vienna in 1529 and again during the second siege in 1683.
Watch this Video:
www.your-friend.info/vienna/travel.html#steffel (walk up 343 stairs and enjoy the panorama view over the city)
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