A discharging arch or relieving arch is an arch

Arch

An arch is a structure that spans a space and supports a load. Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture and their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.-Technical aspects:The...

 built over a lintel

Lintel (architecture)

A lintel can be a load-bearing building component, a decorative architectural element, or a combined ornamented structural item. It is often found over portals, doors, and windows.-Structural uses:...

 or architrave

Architrave

An architrave is the lintel or beam that rests on the capitals of the columns. It is an architectural element in Classical architecture.-Classical architecture:...

 to take off the super incumbent weight. The earliest example is found in the Great Pyramid

Great Pyramid of Giza

The Great Pyramid of Giza is the oldest and largest of the three pyramids in the Giza Necropolis bordering what is now El Giza, Egypt. It is the oldest of the Seven Wonders of the Ancient World, and the only one to remain largely intact...

, over the lintels of the entrance passage to the tomb: it consisted of two stones only, resting one against the other. The same object was attained in the Lion Gate

Lion Gate

The Lion Gate was the main entrance of the Bronze Age citadel of Mycenae, southern Greece. It was erected during the 13th century BC in the northwest side of the acropolis and is named after the relief sculpture of two lionesses in a heraldic pose that stands above the entrance...

 and the Tomb of Agamemnon, both in Mycenae

Mycenae

Mycenae is an archaeological site in Greece, located about 90 km south-west of Athens, in the north-eastern Peloponnese. Argos is 11 km to the south; Corinth, 48 km to the north...

, and in other examples in Greece

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

, where the stones laid in horizontal courses, one projecting over the other, left a triangular hollow space above the lintel of the door, which was subsequently filled in by vertical sculptured stone panels.

The Romans

Ancient Rome

Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

 frequently employed the discharging arch, and inside the portico of the Pantheon

Pantheon, Rome

The Pantheon ,Rarely Pantheum. This appears in Pliny's Natural History in describing this edifice: Agrippae Pantheum decoravit Diogenes Atheniensis; in columnis templi eius Caryatides probantur inter pauca operum, sicut in fastigio posita signa, sed propter altitudinem loci minus celebrata.from ,...

 the architraves have such arches over them. In the Golden Gateway of the palace of Diocletian

Diocletian

Diocletian |latinized]] upon his accession to Diocletian . c. 22 December 244  – 3 December 311), was a Roman Emperor from 284 to 305....

 at Split

Split (city)

Split is a Mediterranean city on the eastern shores of the Adriatic Sea, centered around the ancient Roman Palace of the Emperor Diocletian and its wide port bay. With a population of 178,192 citizens, and a metropolitan area numbering up to 467,899, Split is by far the largest Dalmatian city and...

 the discharging arches, semicircular in form, were adopted as architectural features and decorated with moulding

Molding (decorative)

Molding or moulding is a strip of material with various profiles used to cover transitions between surfaces or for decoration. It is traditionally made from solid milled wood or plaster but may be made from plastic or reformed wood...

s. The same is found in the synagogue

Synagogue

A synagogue is a Jewish house of prayer. This use of the Greek term synagogue originates in the Septuagint where it sometimes translates the Hebrew word for assembly, kahal...

s in Palestine

Palestine

Palestine is a conventional name, among others, used to describe the geographic region between the Mediterranean Sea and the Jordan River, and various adjoining lands....

 of the 2nd century; and later, in Byzantine

Byzantine architecture

Byzantine architecture is the architecture of the Byzantine Empire. The empire gradually emerged as a distinct artistic and cultural entity from what is today referred to as the Roman Empire after AD 330, when the Roman Emperor Constantine moved the capital of the Roman Empire east from Rome to...

 architecture, these moulded archivolt

Archivolt

An archivolt is an ornamental molding or band following the curve on the underside of an arch. It is composed of bands of ornamental moldings surrounding an arched opening, corresponding to the architrave in the case of a rectangular opening...

s above an architrave constitute one of the characteristics of the style. In the early Christian

Christian

A Christian is a person who adheres to Christianity, an Abrahamic, monotheistic religion based on the life and teachings of Jesus of Nazareth as recorded in the Canonical gospels and the letters of the New Testament...

 churches in Rome, where a colonnade

Colonnade

In classical architecture, a colonnade denotes a long sequence of columns joined by their entablature, often free-standing, or part of a building....

 divided off the nave

Nave

In Romanesque and Gothic Christian abbey, cathedral basilica and church architecture, the nave is the central approach to the high altar, the main body of the church. "Nave" was probably suggested by the keel shape of its vaulting...

 and aisles, discharging arches are turned in the frieze

Frieze

thumb|267px|Frieze of the [[Tower of the Winds]], AthensIn architecture the frieze is the wide central section part of an entablature and may be plain in the Ionic or Doric order, or decorated with bas-reliefs. Even when neither columns nor pilasters are expressed, on an astylar wall it lies upon...

just above the architraves.