Editing Gothic architecture (section)

===Flying buttresses===
{{main|Flying buttress}}
An important feature of Gothic architecture was the [[flying buttress]], a half-arch outside the building which carried the thrust of weight of the roof or vaults inside over a roof or an aisle to a heavy stone column. The buttresses were placed in rows on either side of the building, and were often topped by heavy stone pinnacles, both to give extra weight and for additional decoration.<ref name="ReferenceB">{{Britannica |32952 |Western architecture}}</ref>

Buttresses had existed since Roman times, usually set directly against the building, but the Gothic vaults were more sophisticated. In later structures, the buttresses often had several arches, each reaching in to a different level of the structure. The buttresses permitted the buildings to be both taller, and to have thinner walls, with greater space for windows.<ref name="ReferenceB"/>

Over time, the buttresses and pinnacles became more elaborate supporting statues and other decoration, as at [[Beauvais Cathedral]] and [[Reims Cathedral]]. The arches had an additional practical purpose; they contained lead channels which carried rainwater off the roof; it was expelled from the mouths of stone [[gargoyles]] placed in rows on the buttresses.{{sfn|Ducher|1988|pp=50–51}}

Flying buttresses were used less frequently in England, where the emphasis was more on length than height. One example of English buttresses was [[Canterbury Cathedral]], whose choir and buttresses were rebuilt in Gothic style by William of Sens and William the Englishman.<ref name=EBWoS/> However, they were very popular in Germany: in [[Cologne Cathedral]] the buttresses were lavishly decorated with statuary and other ornament, and were a prominent feature of the exterior.

<gallery widths="160" heights="190">
File:Canterbury Cathedral 04.JPG|[[Canterbury Cathedral]] with simple wall buttresses and flying buttresses (rebuilt into Gothic 1174–1177)
File:Lincoln, UK - panoramio (30).jpg|East end of [[Lincoln Cathedral]], with wall buttress, and chapter house with flying buttresses. (1185–1311)
File:Notre Dame buttress.jpg|Flying buttresses of [[Notre Dame de Paris]] ({{Circa|1230}})
File:Amiens Cathédrale Notre-dame arc-boutant sud-est 4.jpg|Buttresses of [[Amiens Cathedral]] with pinnacles to give them added weight (1220–1266)
File:Strebewerk-2.jpg|Section of [[Reims Cathedral]] showing the three levels of each buttress (1211–1275)
File:Koelner dom blick nach osten.jpg|Decorated buttresses of [[Cologne Cathedral]] (1248–1573)
</gallery>

[[File:Cathédrale de Rouen vue de l'Opéra.JPG|thumb|[[Rouen Cathedral]] from the south west – façade towers 12th–15th century, the flamboyant tower to the 15th century, spire rebuilt in 16th century]]