The hotel, originated as a 12thc. manor house, of which the S and W ranges survive, together with a mid-12thc. doorway. Much of the remainder of the site was erected in the late 14thc. (see VII History).

Amberley Castle originated as a manor house, built by the bishops of Chichester to the W of St Michael's church (qv), probably in the 12thc. The main range of the house was aligned N-S, with the hall occupying a wing which projected from the centre to the W. Of this house, the S and W wings survive. The mid-12thc. doorway in the W wing is the earliest identifiable feature; other details here seem to date from the early 13thc. The imposing curtain wall and gatehouse were built shortly after 1377, when Bishop Rede was granted a license to crenellate. Bishop Rede also added the (now part-ruined, part-rebuilt) Great Hall to the NW of the old house, dividing the area within the castle into the Lower Court (W) and Upper Court (E). The castle became a hotel and restaurant in 1988.

A photograph in the NMR Red Boxes shows the doorway prior to its restoration, which involved the reconstruction of the inner arch, and the central segment of the outer arch. These had clearly been removed at some time to create a higher opening.

The chevron is comparable with the W doorway of East Lavant (West Sussex), and both can be datedc.1150. It is not clear whether this doorway, now lying at the W end of the N wall of the Dining Hall, is in its original position or not. The sequence of enlargement and restoration suggests that it is probably in situ.