The Metropolitan Cathedral of Saints Vitus, Wenceslaus and Adalbert (Czech: metropolitní katedrála svatého Víta, Václava a Vojtěcha) is a Roman Catholic metropolitan cathedral in Prague, the seat of the Archbishop of Prague. Until 1997, the cathedral was dedicated to Saint Vitus, and is still commonly referred to only as St. Vitus Cathedral.
This cathedral is a prominent example of Gothic architecture and is the largest and most important church in the country. Located within Prague Castle and containing the tombs of many Bohemian kings and Holy Roman Emperors, the cathedral is under the ownership of the Czech government as part of the Prague Castle complex. Cathedral dimensions are 124 by 60 meters (407 ft × 197 ft), the main tower is 102.8 meters (337 ft) high, front towers 82 meters (269 ft), arch height 33.2 meters (109 ft).
The current cathedral is the third of a series of religious buildings on the site, all dedicated to St. Vitus. The first church was an early Romanesque rotunda founded by Wenceslaus I, Duke of Bohemia in 930. This patron saint was chosen because Wenceslaus had acquired the holy relic – the arm of St. Vitus – from Emperor Henry I. It is also possible that Wenceslaus , wanting to convert his subjects to Christianity more easily, chose a saint whose name (Svatý Vít in Czech) sounds very much like the name of Slavic solar deity Svantevit. Two religious populations, the increasing Christian and decreasing pagan community, lived simultaneously in Prague castle at least until the 11th century.
In the year 1060, as the bishopric of Prague was founded, prince Spytihněv II embarked on building a more spacious church, as it became clear the existing rotunda was too small to accommodate the faithful. A large and more representative Romanesque basilica was built in its spot. Though still not completely reconstructed, most experts agree that it was a triple-aisled basilica with two choirs and a pair of towers connected to the western transept. The design of the cathedral nods to Romanesque architecture of the Holy Roman Empire, most notably to the abbey church in Hildesheim and the Speyer Cathedral. The southern apse of the rotunda was incorporated into the eastern transept of the new church because it housed the tomb of St. Wenceslaus, who had by now become the patron saint of the Czech princes. The bishop’s mansion was also built south of the new church, and was considerably enlarged and extended in the mid 12th-century.
Construction of the present-day Gothic Cathedral began on 21 November 1344, when the see of Prague was elevated to an archbishopric. King John of Bohemia laid the foundation stone for the new building.  The patrons were the chapter of the cathedral (led by Dean), the Archbishop Arnost of Pardubice, and, above all, Charles IV, King of Bohemia and soon to be Holy Roman Emperor, who intended the new cathedral to be a coronation church, family crypt, treasury for the most precious relics of the kingdom, and the last resting place cum pilgrimage site of patron saint Wenceslaus. The first master builder was a Frenchman Matthias of Arras, summoned from the Papal Palace in Avignon. Matthias designed the overall layout of the building, basically an import of French Gothic: a triple-naved basilica with flying buttresses, short transept, five-bayed choir and decagon apse with ambulatory and radiating chapels. However, I lived to build only the easternmost parts of the choir: the arcades and the ambulatory. The slender verticality of late French Gothic and clear, almost rigid respect of proportions distinguish his work today.
After Matthias’ death in 1352, 23-year-old Peter Parler assumed control of the cathedral workshop as master builder. He was son of the architect of the Heilig-Kreuz-Münster in Schwäbisch Gmünd. Initially, Parler only worked on plans left by his predecessor, building the sacristy on the north side of the choir and the chapel on the south. I have finished all that Matthias left unfinished, I have continued according to his own ideas. Parler’s bold and innovative design brought in a unique new synthesis of Gothic elements in architecture. This is best exemplified in the vaults and designed for the choir. The so-called Parler’s vaults or net-vaults have double (not single, as in classic High Gothic groin vaults) diagonal ribs that span the width of the choir-bay. The crossing pairs of ribs create a net-like construction (hence the name), which considerably strengthens the vault. They also give a lively ornamentation to the ceiling, as the interlocking vaulted bays create a dynamic zigzag pattern the length of the cathedral.
While Matthias of Arras was schooled as a geometer, thus putting an emphasis on rigid systems of proportions and clear, mathematical compositions in his design, Parler was trained as a sculptor and woodcarver. He treated architecture as a sculpture, almost as if playing with structural forms in stone. Aside from its bold vaults, the peculiarities of its work can also be seen in the design of pillars (with classic, bell-shaped columns which were almost forgotten by High Gothic), the ingenious dome vault of new St Wenceslaus chapel, the undulating clerestory walls, the original window tracery (not two of his windows are the same, the ornamentation is always different) and the blind tracery panels of the buttresses. Architectural sculpture was given a considerable role while the parler was in charge of construction, the can be seen in the corbels, the passageway lintels, and, particularly, in the busts on the triforium, which depict faces of the royal family, saints, Prague bishops , and the two master builders, including Parler himself.
Work on the cathedral, however, proceeded slowly, because the Emperor commissioned Parler with many other projects, such as the construction of the new Charles Bridge in Prague and many churches throughout the Czech realm. By 1397, when Peter Parler died, only the choir and parts of the transept were finished.
View of the Cathedral and Prague Castle, above the river Vltava.
After Peter Parler’s death in 1399 his sons, Wenzel Parler and particularly Johannes Parler, continued his work; they were in turn succeeded by a certain Master Petrilk, who by all accounts was also a member of Parler’s workshop. Under these three masters, the transept and the great tower on its south side were finished. So it was the gable which connects the tower with the south transept. Nicknamed ‘Golden Gate’ (likely because of the golden mosaic of Last Judgment depicted on it), it is through this portal that the kings entered the cathedral for coronation ceremonies.
The entire building process came to a halt with the beginning of Hussite War in the first half of the 15th century. The war brought an end to the workshop that operated steadily over for almost a century, and the furnishings of cathedral, dozens of pictures and sculptures, suffered heavily from the ravages of Hussite iconoclasm. As if this was not enough, a great fire in 1541 heavily damaged the cathedral.