In 1433, Stephansdom's south tower reached its final height of 136.7m. Today, you can ascend the 343 steps to a small platform for one of Vienna’s most-spectacular views over the rooftops of the Innere Stadt; you don't need a tour ticket for the main nave. When the foundation stone for the south tower was laid in 1359, Rudolf IV is said to have used a trowel and spade made of silver.
Two towers were originally envisaged for the cathedral, but the Südturm grew so high that little space (and funding) remained for the northern one.