Domus Transitoria

The Domus Transitoria was Roman Emperor Nero's first palace destroyed by the Great Fire of Rome in 64 AD, and then replaced by his Domus Aurea (or Golden House).

The palace was intended to connect all of the imperial estates, which had been acquired in various ways, with the Palatine including the Horti of Maecenas and Horti Lamiani, Lolliani, etc.

According to Suetonius (Nero 31.1): "He built a palace extending all the way from the Palatine to the Esquiline, which at first he called the Domus Transitoria, but when it was burned down shortly after its completion and rebuilt, the Golden House".

A few isolated parts of the palace have been discovered but the overall plan remains unclear.

5 metres below Hadrian's Temple of Venus and Rome a sumptuous rotunda belonging to the palace was discovered in 1828, cut through by foundations of the Domus Aurea.

Another part is thought to be on the western side of the Oppian Hill under the Baths of Trajan.

The brick walls of the palace were originally covered with marble at the bottom, while the upper parts were frescoed. A portico was in front of the domus along the south side. Almost all of the columns, floors and marble walls were removed when Trajan gave orders to build his baths (in 104 AD).

Inside is a big courtyard with porticos on three sides, while the fourth on the north consisted of a cryptoporticus which supported the rear embankment. At the centre of the courtyard, occupied now by a series of long wall to support the overlying trajanic baths are the remains of a fountain; on the eastern part is a large grotto that opens to the courtyard.

An elaborate nympheum was unfortunately divided in two by a wall of Trajan. Surrounded by a portico of four columns it was equipped with a cascading fountain on the bottom, whose water was conveyed into a central basin. On the walls of the grotto was a mosaic of which only few traces remain within a frame of shells. The lower part of the walls were originally covered in marble.

The decoration of the vault, 10 m high, is preserved only in part where four corner medallions and a central octagon were inserted, the latter partly preserved representing the Polyphemus scene.

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Wikipedia