The cathedral was first built as a parish church, in 1147, and rebuilt and enlarged over the centuries, with major new work concluding in 1511, although repair and restoration have continued from the beginning to the present day.
 

It was previously thought that the church had been built in an open field outside the city walls; but excavations for a long-awaited heating system during 2000 revealed graves that were carbon-dated to the fourth century, 8 feet (2.5 meters) below the surface. The 430 skeletons were then moved to the catacombs. Thousands of others must have been buried in the ancient cemetery of this neighborhood, starting in Roman times; and this, instead of St. Ruprecht's Church, may be the oldest church site in Vienna.
The first recorded church here was founded in 1137, by Duke Leopold IV in a contract with Reginmar, Bishop of Passau. The church was dedicated to St. Stephen, the patron of the bishop's cathedral in Passau. The first church building was built in the Romanesque style and consecrated ten years later. The present west wall and Roman towers date from 1237. After a great fire in the city in 1258, a larger replacement structure, also Romanesque and reusing the Roman towers, was consecrated, on 23 April 1263, an anniversary highlighted each year by a rare ringing of the Pummerin bell for three minutes in the evening.

In 1304, Emperor Albert I ordered construction of a Gothic three-naved choir, further east of the church and wide enough to meet the tips of the old transepts. Work continued under his son Duke Albert II; this latest work was consecrated in 1340, on the 77th anniversary of the previous consecration. The motif of the north nave furnishings was St. Mary; the middle nave was for St. Stephen and All the Saints; and the Apostles were honored in the south nave. This part of the present cathedral, east of the present transepts, is called the Albertine Choir. In 1359, his son Duke Rudolf IV, who is called "the founder", laid, in the vicinity of the present south tower, the cornerstone for a Gothic extention of Albert's choir westward, to encapsulate the existing second church. That old church was then removed from inside the new one.
The Stephansdom was saved from intentional destruction at the hands of retreating German forces during World War II, when Captain Gerhard Klinkicht disregarded orders from the city commandant, Sepp Dietrich, to "fire a hundred shells and leave it in just debris and ashes". One of the fires set by plunderers when Russian troops entered the city was carried by the wind to the cathedral, severely damaging it on 12 April 1945. Fortunately, protective brick shells had been built around the Pulpit, Frederick III's tomb, and other treasures, so that damage to the most valuable artworks was minimzed. Unfortunately, the beautifully carved choir stalls from 1487 were burned. Rebuilding began immediately, with a limited reopening on 12 December 1948 and a full reopening on 23 April 1952.

The Romanesque and gothic cathedral is 107 meters (351 feet) long and 34 meters (111.5 feet) wide. The soot accumulated over centuries has been removed in recent years, changing it from a black-colored structure to a white one.

Towers

The massive south tower (at location ST on the Plan below) is the dominant feature of the Vienna skyline at 136 meters (445 feet) and is affectionatly called Steffl ("Steve") by the Viennese. It served as the main observation and command post for the defense of the walled city during the Siege of Vienna in 1523 and again during the second siege in 1683. It is as much the most recognized symbol of Vienna as the Eiffel Tower is of another city. Its construction took 65 years to complete, from 1368 to 1433, and it contains an apartment for the watchmen who, for centuries (ending in 1955), manned the tower during the night to ring its bells if they spotted a fire. The tip of the tower has the double eagle imperial emblem with the Habsburg-Lorraine coat of arms on its chest, surmounted by the double-armed apostolic cross symbolic of the emperors' style Apostolic Majesty as kings of Hungary.

The north tower (at location NT), planned as a twin to the south tower, has not been completed and is only half as tall, at 68 meters (223 feet). It was given a temporary cap that the Viennese call the "water tower top" when its construction paused in 1511. Construction has not yet resumed.

On the left and on the right from the main entrance are the two Roman towers (at locations RT on the Plan below) which are about 65 meters (215 feet) tall. They are called "Roman" (heidnischen in old Viennese dialect) because they were built from rubble of structures built by the Romans during their occupation of the city site. Square at their bases, and octagonal when the rise above the roof, they housed bells, and although the south Roman tower lost its bells during World War II, the north one is still a working bell tower. Along with the Giant Door, they are the oldest parts of the church.

Roof

A glory of the Stephansdom is its ornately patterned, richly colored roof, 110 meters (361 feet) long, and covered by 230,000 glazed tiles. Above the choir, on one side of the building the tiles form a mosaic of the double-headed eagle that is symbolic of the empire ruled from Vienna by the Habsburg dynasty, and on the other the coats of arms of the City of Vienna and of the Republic of Austria are depicted. In 1945, fire caused by World War II damage to nearby buildings lept to the north tower of the Stephansdom and went on to destroy the roof. Replicating the original bracing for so large a roof (it rises 38 meters above the top of the walls) would have required an entire square kilometer of forest, so over 600 metric tons of steel bracing were used instead. The roof is so steep (an 80-degree pitch in some areas) that it is sufficiently cleaned by the rain alone and is never covered by snow.
 

Bells

The cathedral has 23 bells. The largest is officially named for St. Mary, but usually called Pummerin ("Boomer") and hangs in the north tower. At 20,130 kilograms (44,380 pounds), it is the largest in Austria and the second largest swinging bell in Europe (after the 23,500-kilogram (51,800-pound) Peter in Cologne Cathedral). Originally cast in 1711 from cannons captured from the Muslim invaders, it was recast (partly from its original metal) in 1951 after crashing onto the floor when its wooden cradle burned during the 1945 fire. The new bell has a diameter of 3.14 meters (9.6 feet) and was a gift from the province of Upper Austria. It sounds on only a few special occasions each year, including the arrival of the new year. There are three other bells hanging in this tower, but they are older and no longer used.
A peal of eleven electrically operated bells, cast in 1960, hangs in the soaring south tower. Replacements for other ancient bells also lost in the 1945 fire, they are used during Masses at the cathedral: four are used for an ordinary Mass; the quantity increases to as many as ten for a major holiday Mass; and the eleventh and largest is added when the Cardinal Archbishop of Vienna himself is present. From the largest to the smallest, they are named the St. Stephen (5,700 kg); St. Leopold (2,300 kg); St. Christopher (1,350 kg); St. Leonhard (950 kg); St. Josef (700 kg); St. Peter Canisius (400 kg); St. Pius X (280 kg); All Saints (200 kg); St. Clement Maria Hofbauer (120 kg); St. Michael (60 kg); and St. Tarsicius (35 kg). Also in this tallest tower are the Primglocke (recast in 1772) and the Uhrschälle (cast in 1449), which mark the passing of the hours.

The north Roman tower contains six bells, five of which were cast in 1772, that ring for evening prayers and toll for funerals. They are working bells of the cathedral and their names usually recall their original uses: Feuerin ("fire alarm" but now used as a call to evening prayers) cast in 1859; Kantnerin (calling the cantors (musicians) to Mass); Feringerin (used for High Mass on Sundays); Bieringerin ("beer ringer" for last call at taverns); Poor Souls (the funeral bell); and Churpötsch (donated by the local curia in honor of the Maria Pötsch icon in the cathedral).
The 1945 fire destroyed the bells that hung in the south Roman tower. It is said that the composer Ludwig van Beethoven discovered the totality of his deafness when he saw birds flying out of the bell tower as a result of the bells' tolling but couldn't hear the bells.
 

Interior

Plan of the cathedral, with features mentioned in this article marked with red letters. CT "Christ with a Toothache" sculpture; Fr3 Tomb of Emperor Frederick III; G Giant Door HA High Altar; MP Maria Pötsch icon; NT North Tower; P Pulpit; PES Prince Eugene of Savoy burial chapel; RT Roman Towers; S Sundial; SJC Saint John of Capistrano pulpit; ST South Tower; WNA Wiener Neustädter Altar

A masterwork of late gothic sculpture is the stone pulpit. Long attributed to Anton Pilgram, today Niclaes Gerhaert van Leyden is thought more likely to be the carver. So that the local language sermon could be better heard by the worshipers in the days before microphones and loud speakers, the pulpit stands against a pillar out in the nave, instead of in the chancel at the front of the church. The sides of the pulpit erupt like stylized petals from the stem supporting it. On those gothic petals are relief portraits of the four original Doctors of the Church (St. Augustine of Hippo, St. Ambrose, St. Gregory the Great and St. Jerome), each of them in one of four different temperments and in one of four different stages of life.

The handrail of the stairway curving its way around the pillar from ground level to the pulpit has decorations of toads and lizards biting each other, symbolizing the fight of good against evil. At the top of the stairs, a stone puppy protects the preacher from intruders. Beneath the stairs is one of the most beloved symbols of the cathedral: a stone self-portrait of the unknown sculptor gawking (Ger. "gooken") out of a window (Ger. "fenster") and thus famously known as the Fenstergucker.

Text Source: Wikipedia
 

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