Romanesque architecture is often divided into two periods: the "First Romanesque" style and the "Romanesque" style. The difference is chiefly a matter of the expertise with which the buildings were constructed. The First Romanesque builders often employed rubble walls, smaller windows and unvaulted roofs. A greater refinement marks the Second Romanesque, along with increased use of vaults and expertly dressed stone.
Combining features of Western Roman and Byzantine buildings, Romanesque architecture is known by its massive quality, its thick walls, round arches, sturdy piers, groin vaults, large towers and decorative arcading. Each building has clearly defined forms and they are frequently of very regular, symmetrical plan so that the overall appearance is one of simplicity when compared with the Gothic buildings that were to follow. The style can be identified right across Europe, despite regional characteristics and different materials.
Stone sculpture, with some notable exceptions, such as the great crosses of the British Isles, had almost disappeared from the art of western Europe during the early Middle Ages. The revival of stonecarving is a hallmark of the Romanesque age--and one reason the period is aptly named. The inspiration for stone sculpture no doubt came, at least in part, from the abundant remains of ancient statues and reliefs throughout rome's northwestern provinces.
The principal countries in which Romanesque architecture flourished were France, England, Italy, Germany, and Spain. In all these countries political conditions were in a state of turbulence; the southern half of Spain was still in the hands of the Moors. Such absence of political unity, combined with other factors--widespread iliteracy, small and scattered populations and poor communications--favoured the evolution of local styles so divergent, even within a single country, that it is sometimes a problem to determine whether or not all of them may be accurately described as Romanesque.
The Romanesque style of church had many failures. They were rather dark on the inside because the high walls would not support large openings for windows. The wall were very thick. The arches were rounded and as such would not tolerate a lot of weight without crumbling. There was the need for larger and larger churches by the time of Charlemagne.
Gothic Cathedrals were extremely tall and filled with light coming through stained glass windows, giving church-goers the feeling that they had entered a very heavenly realm. Romanesque churches, on the other hand, were very heavy and sober, and reflected the serious religious fervor in fear of the rapture.
Thus when William Gunn in 1819 first applied the term "Romanesque" to architecture, he used it to cover all the masonry buildings of Western Europe between the Roman period and the Gothic. To underline the parallel with the languages, he cited the difference drawn in the Rome of his day between a "Romano", someone who was unarguably a citizen, and a "Romanesco", an inhabitant of dubious origins. Romanesque therefore meant "not properly Roman", or literally "Roman-ish".
In the southern regions of the Holy Roman Empire, the classical heritage of Rome heavily influenced Romanesque architecture. Italian cities developed their own versions of Romanesque architecture, retaining a strong reliance on the classical past with little influence from northern Europe. In general, the Early Christian basilica remained the standard church form, seldom having a westwerk or attached towers as in Ottonian or Carolingian architecture.
The layouts of Romanesque churches were very simple, usually in crucifex form with the nave in the center and the ambulatory at the head, or the "top" of the cross. As Gothic architeture developed, layouts became more complicated. You can see examples here: http://web.archive.org/web/20090624065547/http://www.owlnet.rice.edu/~hart205/Cathedrals/Plan/plan.html
In erecting their walls, the Romanesque builders followed the example of the Romans. They made use of small materials, in contrast to the great blocks of stone and marble favoured by the Greeks. The main body of their walls was of course worksmanship, frequently consisting of rubble--pieces of stone of any shape and size bound together by mortar. But the roughness of such work was usually concealed by a facing of neatly laid flat stones, plaster, or marble.
Sadly, much of the great developments of the Romanesque period are overshadowed by later works. When we think of the Norman style today, we think more of fortified walls and castles. But, the careful student will be greatly rewarded by turning attention toward the abbeys and monasteries of the pre-Gothic age. The needs of the large monastic orders for housing, industry and religious service ignited a strong demand for new building skills and techniques. Although they do not receive as much public attention as the grand churches and cathedrals, many of the Cistercian and Benedictine abbeys still exist.
The style of Architecture immediately preceding Gothic within Europe, is known as Romanesque. Such structures are generally contained within the eleventh and twelfth centuries. This distinctive style drew many of its early forms from the previous Carolingian period which began during the reign of great Charlemagne. The name literally refers to the intent of designing in the style or manner of Rome.