St. Stephen's Cathedral, or Stephansdom, is an iconic Gothic masterpiece located in Vienna, Austria. Completed in the 12th century, it features the stunning multi-coloured tile roof and a towering spire reaching 136 metres. This cathedral houses the largest bell in Austria, known as Pummerin, and has witnessed significant historical events. Visitors can explore its magnificent interior, including beautiful chapels and artworks, while enjoying panoramic views from its observation deck. It remains a must-see landmark for anyone visiting Vienna.