The exploitation of the arch as both a structural and decorative device revolutionized architecture, making possible the building of much larger structures than those allowed by post-and-lintel construction.

Although the structural benefits of the arch were known as early as 3500 b.c.e., both the Egyptians and later the Greeks chose a simpler form of construction. As they adapted the Greek orders, so too the Romans took the structural form of the arch and exploited it throughout the Roman Empire. Through numerous barbaric invasions the arch remained a symbol of civilization long after the power of Rome disappeared. Augustus

The earliest architects used post-and-lintel construction to create the first shelters. In this type of structure, weight is not distributed on the posts but is placed directly on the lintel, thus limiting a structure’s height, weight of materials, and number of stories. Large structures required massive pieces of stone and an equally massive labor force. In 3500 b.c.e., Egyptian architects began experimenting with vaults at both Dendera and Abydos. Constructed of wedge-shaped voussoirs with the joints between radiating from the center, the arch permits weight to be dispersed directly on to the posts. Though this support system proved successful, a rigid artistic tradition relegated the arch to underground storage areas.

As in Egypt, the Greeks chose to perfect post-and-lintel construction. Using weight, iron rods, and exact measurement, architects created what appeared to be seamless monumental structures. The Greek “order” featured a simple post-and-lintel construction of column and entablature, which produced a structure of horizontal and upright stone beams, featuring the colonnade designed to suppress the wall. The Greeks disliked the arch because it gave distinctive form to a hole. It was characteristic of Greek thought to conceive of form or shape as that which determines the reality of what truly exists and to think of space or emptiness as the prime symbol of nonbeing.

The first architects to accord the arched aperture an important role in their construction were the Etruscans. These residents of Latium first used the arch in vaulted drains dating from the fourth century b.c.e. By 240 b.c.e., architects employed this technology for bridges on the Via Amerina and city gates such as the Porta Augusta in Perugia. As the Romans began to gain an upper hand in the struggle for the control of the Italian peninsula, they freely adopted cultural traits from the peoples they conquered.

Unlike either the Egyptians or Greeks, the Romans made the brick their major medium of construction. While such a small building block hampers post-and-lintel construction, it is ideal for the arch. The genius of Roman architecture lay in combining the arch and the Greek orders by building a wall pierced with arches and then placing the Greek colonnade against it, so as to show an arch between two columns that appeared to carry the entablature above. To fully ally the two elements, the impost molding was put around the pier to receive the arch, while the base moldings and the band about the arch echoed the architrave. Finally, a keystone was used as an inventive aesthetic detail to bind the arch and the Greek order at its most critical point. This architectural innovation first appeared at the beginning of the first century b.c.e. in structures such as the Tabularium and the Temple of Hercules Victor at Tivoli.

As their engineering skills increased, the Romans employed the arch in a variety of ways, ranging from the strictly utilitarian Cloaca Maxima and the Pont du Gard to the purely commemorative or monumental arches of triumph. As Rome expanded outside of the Italian peninsula, communication became vital. It was as pontifex maximus or “bridge builder” that the ruler could best visibly assert his authority by binding the empire together with roads and bridges. The scale of public works such as the aqueduct at Segovia, Spain, from the first century c.e., dwarfed earlier Etruscan examples.

The Etruscans first employed the arch in a city gate, but it was the Romans who isolated the gateway as a symbol of power. Augustus ordered the construction of the first triumphal arch at Rimini in 27 b.c.e. to celebrate the restoration of the highway system in northern Italy. The arch thus became a metaphor of the state’s control over the passageway and its ability to regulate and control the citizen’s movements. This idea is enforced by the use of the triumphal arch on imperial coinage beginning during the reigns of the Julio-Claudian Dynasty of Roman emperors (14-37 c.e.).

The pinnacle of Rome’s exploitation of the arch was not visible to the average person, but it did make the grandeur of the imperial city possible. In works such as the Pantheon, begun in 27 b.c.e. by Marcus Vipsanius Agrippa and rebuilt by Hadrian (76-138 c.e.) in c. 118-128 c.e., a series of arches are used as internal buttress that support the domed rotunda. Hidden by the interior design of the building, these arches are then supported by a series of vaulted galleries. The development of the vault forced the column eventually to stand alone below this device because with this form of arch there is no place for an entablature. The first time arches were set directly on capitals of columns with no architrave was in the palace of Diocletian at Spalatum in 300 c.e.

Following the shift of imperial power from the West to the East after the founding of Constantinople in 326-330 c.e., the arch played an important role in attempting to reverse the technical decline of European architecture. In 547 c.e., under Justinian’s plan to reunify the Roman Empire, the Church of Saint Vitale was constructed in Ravenna. Centrally planned, its eight piers rely on two sets of arches to support the gallery and the roof.

Although Justinian’s successors found it unprofitable to maintain the reconquered provinces in the West, Saint Vitale and its combination of the column and arch became an architectural model in Europe for another five hundred years. When Charlemagne began a cultural revival in 800 c.e., he used the architecture of his palace at Aachen, Germany, to express his ties to Rome. His Palatine Chapel, consecrated in 805 c.e., follows the plan of Saint Vitale with a simplified elevation, since a thorough knowledge of Rome’s engineering practices had been lost among western builders. Charlemagne was not alone in his desire to employ Roman forms, because they are clearly apparent in such structures as the abbey gatehouse of Lorsch (near Frankfurt, Germany), which is meant to be a triumphal arch.

By 1140, the Roman arch and many of the vaulting forms developed during the imperial period once more appeared in many of the religious structures of Western Europe. Abbot Suger (1081-1151) made revolutionary use of the flying buttress and pointed arches at Saint-Denis, marking the first intellectual break with Christianity’s architectural past. For the next four hundred years, the arch’s structural and aesthetic uses were combined to create edifices of greater height with multiple window openings which were dedicated to the glory of God.

In 1421, Filippo Brunelleschi’s design for the Foundling Hospital in Florence not only ushered in the Renaissance but also restored the rounded Roman arch to its place as a symbol of civilization. Expanding from Italy, both Imperial and Republican architecture were used by successive generations to express their place on the international political stage.

Although the arch has played a role as a decorative motif in the twentieth century, its last development as a structural form took place in the nineteenth. With the harnessing of steam and industrialization, architects and engineers faced new design problems. For many, Joseph Paxton’s prominent use of the arch in the iron supports of the Crystal Palace demonstrated how a “noble” Roman form could be adapted for modern needs. With the advent of reinforced concrete and steel, however, the arch no longer fulfilled a structural need.

• Jones, Mark Wilson. Principles of Roman Architecture. New Haven, Conn.: Yale University Press, 2003. Explores the design principles used by Roman architects and the ways in which they channeled their creativity. The book is divided into a theoretical section and a set of three case studies of specific monuments.
• MacDonald, William L. The Pantheon: Design, Meaning, and Progeny. 1992. Reprint. Cambridge, Mass.: Harvard University Press, 2002. A close study of the Pantheon and its architectural features, both technological and theoretical, including the use of arches.
• Sear, Frank. Roman Architecture. London: Batsford, 1989. A fundamental, illustrated account integrating the arch into the development of Roman architecture.
• Thorpe, Martin. Roman Architecture. London: Bristol Classical Press, 1995. Thorpe illustrates the vast subject of Roman architecture by focusing on several important examples.