Early in the 5th year of his reign, Amenhotep IV decided to cut all links with the traditional religious capital of Egypt and its god Amun, and to build an entirely new city on virgin soil that would be devoted solely to the cult of Aten. At the same time, he changed his name to Akhenaten, probably meaning 'Creative Manifestation of the Aten'. The new city, nowadays known as Amarna, was called Akhetaten 'Horizon of the Aten', that is the place where the Aten manifests himself and where he acts through his son, the King. The King set up some boundary stelae defining the territory of Akhenaten. We do not know when exactly the King took up residence in Akhetaten, but presumably it was within a year or two of its foundation.
As soon as the decision to move had been made, all building activities at Thebes ceased. And the king's original name was removed from the inscriptions and replaced by the new one. Once Akhenaten was firmly settled in his new residence, a further radicalization of his religious reforms took place. In the 9th year, the official name formula of Aten was changed to 'the Living One, Re, Ruler of the Horizon who Rejoices in the Horizon in his Identity of Re the Father who has Returned as the Sun-disc'. Probably at the same time as this name's change took place, the traditional gods were banned completely and a campaign was launched to remove their names and effigies (particularly those of Amun) from the monuments. The traditional state temples were closed down and the cults of their gods came to a standstill: the religious festivals with their processions and public holidays were no longer celebrated either.

 The art of Amarna

The earliest representations of Amenhotep IV show him in a traditional style closely resembling the one used to portray Thutmosis IV and Amenhotep III, but not long after his accession Amenhotep IV had himself depicted with a thin, long face with pointed chin and thick lips, an elongated neck, a round protruding belly, wide hips, fat thighs and thin legs. During the early years at Amarna, the king's features were depicted in such an exaggerated way. Later during his reign, a more balanced style developed. It was not only Akhenaten, Nefertiti, and their daughters who were depicted in this style, but all other courtiers who existed at that time. This is not surprising, since representations of private individuals had always followed the artistic model of the king of their time. The extraordinary manner in which Akhenaten portrayed himself and his family on his monuments somehow reflects the King's actual physical appearance, although in an exaggerated style, according to one opinion. Scenes of the royal family display an intimacy that had never been shown before in Egyptian art even among private individuals.
Another characteristic feature of the Amarna style is its extraordinary sense of movement and speed, and its freedom of expression that was to have a lasting influence on Egyptian art for centuries after the Amarna Period had come to an end. Speed is also the determining factor of a new building technique. Again, the earliest structures of Amenhotep IV employed the traditional large sandstone blocks commonly used for temple walls, but these were soon replaced (in both Thebes and Amarna) by very much smaller blocks, the so-called 'talatat', typically measuring about 60 x 25 cm and therefore small enough for a single man to lift and carry. This made it much easier to erect a large building in a relatively short span of time. The new method was abandoned again after the Amarna Period, perhaps because it had by then become apparent that the reliefs carved on the walls constructed of such small blocks did not stand time like the traditionally built walls. Certainly Akhenaton's successors soon found that it also took far less time and effort to demolish buildings constructed of talatat.Aten, a New GodAmenhotep IV began his reign with a major building programme at Karnak, the very centre of the cult of Amun. The temples that he started to build there at Karnak, perhaps situated to the east of the Amun precinct and orientated towards the East, were not dedicated to Amun but to a new form of the Sun-god whose name was 'the Living One, Re-Horus of the Horizon who Rejoices in the Horizon on his Identity of Light which is in the Sun-disc', a long formula that was soon enclosed in two cartouches just like the names of a king, and that was often preceded in royal inscriptions by the words 'My Father Lives' .
The name of the god could be shortened to 'the Living Sun-disc' or simply 'the Sun-disc' (in Egyptian the 'Aten'). The word itself was not new; it had previously been used to refer to the visible celestial body of the Sun. During the reign of Amenhotep III, this aspect of the Sun-god had become increasingly important, especially in the later years of his reign. During the King's Sed-festivals, his deified self had been identified with the Sun-disc and in several inscriptions, most clearly in one of them on the back pillar of a recently discovered statue, the King calls himself 'the Dazzling Aten'. Originally this new form of the Sun-god was depicted in the traditional manner: as a man with a falcon's head surmounted by a sun-disc, but early in the reign of Amenhotep IV this form was abandoned in favor of a radically new way of depicting a god - as a disc with rays ending in hands that touch the king and his family, extending symbols of life and power towards them and receiving their offerings.