Stephansdom is Vienna's zero point — the Gothic cathedral whose 136-metre south tower, the "Steffl", was the tallest structure in the city for over 500 years, and whose roof of roughly 230,000 glazed tiles spells out a double-headed Habsburg eagle in chevron patterns. The current building went up between the 14th and 15th centuries over a Romanesque predecessor whose Giant's Door and Heathen Towers still form the west front. Mozart married Constanze Weber here in 1782; his funeral service was held in the Crucifix Chapel in 1791.
Entering the nave is free, but the four paid extras are where the cathedral opens up. The south tower is a 343-step spiral climb (about €6, no lift) to a watchman's room with rooftop views across the tiled roof. The north tower has a lift (about €7) up to the Pummerin, Austria's largest bell, cast partly from cannons abandoned by the Ottoman army in 1683. The catacombs tour descends past bishops' crypts and the urns holding Habsburg entrails — the dynasty split its dead between three churches. An all-inclusive ticket bundling towers, catacombs and audio guide runs about €25.
Visit before 09:00 or during early evening to see the nave without crowds; tourist access is restricted during Mass (Sunday mornings especially). Stephansplatz outside sits directly above its own U-Bahn station where the U1 and U3 cross, making the cathedral the natural start of any 1st-district walk — the Graben, Kärntner Straße and the Hofburg all fan out from here.
