After the decline of the Roman Empire, the building of large churches in Western Europe gradually gained momentum with the spread of organized monasticism under the rule of Saint Benedict and others. A huge monastery at Cluny, only a fraction of which still exists, was built using a simplified Roman style, stout columns, thick walls, small window openings and semi-circular arches. The style spread with monasticism throughout Europe. The technique of building high vaults in masonry was revived. A treatment of decoration evolved that had elements drawn from local Pre-Christian traditions and incorporated zigzags, spirals and fierce animal heads. The typical wall decorations were painted murals. The Romanesque building techniques spread to England at about the time of the Norman conquest.
Representative of the period are Abbaye aux Hommes (the Abbey of the Men) in Caen, France; Worms Cathedral in Germany, the Cathedral of Pisa with its famous leaning campanile (bell tower), Modena Cathedral and the Parma Cathedral in Italy, and Durham Cathedral and Peterborough Cathedral in England.
Saint-Georges de Boscherville Abbey, France, has a square tower over the crossing. The western pinnacles are in the Gothic style.
Speyer Cathedral, Germany, from the east, shows the apse projecting from a chancel framed by towers, with an octagonal dome over the crossing.
Pisa Cathedral, Italy, has a free-standing campanile and presents a harmony of polychrome and arcades.
Romanesque interiors
San Miniato al Monte, Florence, has basilical form, open timber roof and decoration of polychrome marble and mosaic.
The Church of St Philibert, Tournus, has tall circular piers and is roofed with transverse arches supporting a series of barrel vaults.
Vézelay Abbey has clusters of vertical shafts rising to support transverse arches and a groin vault. The east end is Gothic.
The nave of Peterborough Cathedral is in three stages supporting a rare wooden ceiling