With 20,000 seats, the cathedral is the largest, but not the highest, church in Austria. The originally-planned, higher spire was not approved, because in Austria-Hungary at the time, no building was allowed to be taller than the South Tower of the St. Stephen's Cathedral in Vienna. The New Cathedral was then designed to be less than two meters shorter than the Viennese cathedral....and then they put a 2 meter high cross at top of the spire.