This Page is under development September 2026
The site known as the Nunnery was founded as a Late Roman small fort, probably in the late fourth century AD. It formed part of a chain of fortifications created on both sides of the Channel and along the North sea coast in response to increasing threats to the Roman empire. The fort appears to have remained in use through the early middle ages as Frankish pottery has been found nearby. Known as a ‘castle’ in the high middle ages, it was garrisoned by English troops. At some point in the early modern period, part of the Roman east wall fell onto the beach and the tower either collapsed or was deliberately slighted.
The site became the home of the Tudor governors of Alderney in the late sixteenth century and fell into disuse during the seventeenth. By the eighteenth century it was known as ‘the Nunnery’ and refurbished as an artillery fort by the British army. With increased threat from France, it was substantially remodelled c.1793 with the addition of the buildings still found inside the fort today. It remained garrisoned into the Victorian period where it housed a military hospital. In 1906 it was remodelled again as married quarters for military families. By 1930 the War Office had let it out to a private tenant.
In July 1940 Alderney was occupied by the forces of Nazi Germany and almost all its civilian population were evacuated. The site was extensively modified as resistance point Piratenschloss (pirate castle) as part of Hitler’s Atlantic Wall. After the war the site passed to the States of Alderney who let it to private tenants. Since 2026 it has been back in States ownership and is maintained as a historic site and visitor attraction.
It is not known whether the site was ever, in fact, a nunnery!
A Late Roman Fort on Alderney, Channel Islands, by Jason Monaghan, is published in 2026.
Excavations
Dig Alderney has conducted a series of excavations at the site, which will have their separate pages here. Interim reports on the excavations have been published in the Alderney Society Bulletin.
The updated archive report is available here.
2008
2009
2010
2011
2012
2013
2016
2017-18
2021
2022
Historic periods
at the site are described here.
Roman
Tudor
Eighteenth and Nineteenth Century
German WW2