The form of the Roman temple was mainly derived from the
Etruscan model, but in the late Republic there was a switch to using Greek classical and Hellenistic styles, without much change in the key features of the form. The Etruscans were a people of northern Italy, whose civilization was at its peak in the seventh century BC. The Etruscans were already influenced by early
Greek architecture, so Roman temples were distinctive but with both Etruscan and Greek features. Surviving temples (both Greek and Roman) lack the extensive painted statuary that decorated the rooflines, and the elaborate revetments and
antefixes, in colourful terracotta in earlier examples, that enlivened the
entablature. , part original, with parts restored Etruscan and Roman temples emphasised the front of the building, which followed
Greek temple models and typically consisted of wide steps leading to a
portico with columns, a
pronaos, and usually a triangular
pediment above, which was filled with statuary in the most grand examples; this was as often in
terracotta as stone, and no examples have survived except as fragments. Especially in the earlier periods, further statuary might be placed on the roof, and the entablature decorated with
antefixes and other elements, all of this being brightly painted. However, unlike the Greek models, which generally gave equal treatment to all sides of the temple, which could be viewed and approached from all directions, the side and rear walls of Roman temples might be largely undecorated (as in the
Pantheon, Rome and
Vic), inaccessible by steps (as in the
Maison Carrée and Vic), and even back on to other buildings. As in the Maison Carrée, columns at the side might be
half columns, emerging from ("engaged with" in architectural terminology) the wall. , Split The platform on which the temple sat was typically raised higher in Etruscan and Roman examples than Greek, with up to ten, twelve or more steps rather than the three typical in Greek temples; the
Temple of Claudius was raised twenty steps. These steps were normally only at the front, and typically not the whole width of that. It might or might not be possible to walk around the temple exterior inside (
Temple of Hadrian) or outside the
colonnade, or at least down the sides. The description of the Greek models used here is a generalization of classical Greek ideals, and later Hellenistic buildings often do not reflect them. For example, the "Temple of Dionysus" on the terrace by the theatre at
Pergamon (Ionic, 2nd century BC, on a hillside), had many steps in front, and no columns beyond the portico. The
Parthenon, also approached up a hill, probably had many wide steps at the approach to the main front, followed by a flat area before the final few steps. After the eclipse of the Etruscan models, the Greek
classical orders in all their details were closely followed in the façades of Roman temples, as in other prestigious buildings, with the direct adoption of Greek models apparently beginning around 200 BC, under the late Republic. But the distinctive differences in the general arrangement of temples between the Etruscan-Roman style and the Greek, as outlined above, were retained. However the idealized proportions between the different elements in the orders set out by the only significant Roman writer on architecture to survive,
Vitruvius, and subsequent
Italian Renaissance writers, do not reflect actual Roman practice, which could be very variable, though always aiming at balance and harmony. Following a
Hellenistic trend, the
Corinthian order and its variant the
Composite order were most common in surviving Roman temples, but for small temples like
that at Alcántara, a simple
Tuscan order could be used. Vitruvius does not recognise the Composite order in his writings, and covers the Tuscan order only as Etruscan; Renaissance writers formalized them from observing surviving buildings. or chapel added to
Dendera Temple, using the traditional
Egyptian temple style. The front of the temple typically carried an inscription saying who had built it, cut into the stone with a "V" section. This was filled with brightly coloured paint, usually scarlet or
vermilion. In major imperial monuments the letters were cast in
lead and held in by pegs, then also painted or
gilded. These have usually long vanished, but archaeologists can generally reconstruct them from the peg-holes, and some have been re-created and set in place. Sculptural decoration was similar to that of Greek temples, often with
pedimental sculpture with figures, of which only few fragments survive. However, exterior friezes with figures in relief were much less common. Many
acroteria,
antefixes and other elements were brightly coloured. In the early Empire older Greek statues were apparently sometimes re-used as acroteria. There was considerable local variation in style, as Roman architects often tried to incorporate elements the population expected in its
sacred architecture. This was especially the case in
Egypt and the
Near East, where different traditions of large stone temples were already millennia old. The
Romano-Celtic temple was a simple style, usually with little use of stone, for small temples found in the
Western Empire, and by far the most common type in
Roman Britain, where they were usually square, with an
ambulatory. It often lacked any of the distinctive classical features, and may have had considerable continuity with pre-Roman temples of the
Celtic religion.
Circular plans , from the rear Romano-Celtic temples were often circular, and circular temples of various kinds were built by the Romans. Greek models were available in
tholos shrines and some
other buildings, as assembly halls and various other functions. Temples of the goddess
Vesta, which were usually small, typically had this shape, as in those at Rome and Tivoli (see list), which survive in part. Like the
Temple of Hercules Victor in Rome, which was perhaps by a Greek architect, these survivors had an unbroken colonnade encircling the building, and a low, Greek-style podium. Different formulae were followed in the
Pantheon, Rome and a small temple at
Baalbek (usually called the "Temple of Venus"), where the door is behind a full portico, though very different ways of doing this are used. In the Pantheon only the portico has columns, and the "thoroughly uncomfortable" exterior meeting of the portico and circular
cella are often criticised. At Baalbek, a wide portico with a
broken pediment is matched by four other columns round the building, with the
architrave in scooped curving sections, each ending in a projection supported by a column. At
Praeneste (modern Palestrina) near Rome, a huge pilgrimage complex of the 1st century BC led visitors up several levels with large buildings on a steep hillside, before they eventually reached the sanctuary itself, a much smaller circular building. ==Caesareum==