The comprehensive gazetteer and bibliography of the medieval castles, fortifications and palaces of England, Wales, the Islands.
The listings
Other Info
Print Page 
Next Record 
Previous Record 
Back to list 

Grosnez Castle

In the parish of St Ouen.
On the Isle of Jersey.

Latitude 49.25762° Longitude -2.24661°

Grosnez Castle has been described as a certain Masonry Castle.

There are masonry ruins/remnants remains.

This site is a building or structure protected by law.


On the cliffs at Les Landes, at the most north-westerly point of Jersey you can find the ruins of Grosnez castle, built between 1328 and 1330. Little is known about the history of this roughly built fort. Grosnez- meaning either 'big nose' in modern day Jersey/French Patois or "great headland" (from the Norse word 'ness') - was built to protect the islanders from the French. It was obviously not intended to withstand a siege as water would have to be carried from the nearest spring, 200 yards away. Additionally, there were no secondary walls inside the castle so once the outer walls were breached it's capture was certain. The castle was captured in 1468 and by 1540 it lay in ruins, local legend has it that much of the stone was used to build St. Ouen's Manor. What is known is that locals took down the castle deliberately and used the stones on their own land particulary around the Mont Mado area of St. John from where the stone originally came. What remains today is a gatehouse separated from the mainland by a big ditch and a section of wall. (

Popular refuge. Promontory site, defended by lofty cliffs, irregular ward with round towers and a square gatehouse; inner buildings consisted only of small hutments. Probably built c. 1328 (King 1983)

The understanding of the site and its history is limited due to the lack of any recent documentary or archaeological research. Research into the castle's history was carried out as far back as 1897 (Le Cornu) and more recently in 1926 (Rybot). The archaeology, both structural and below ground, holds a great deal of evidence. Grosnez Castle is a fortified stronghold thought to have been built around 1330 on the orders of the Warden of the Isles, Sir John des Roches, to serve as a refuge from French attack for islanders in this part of Jersey. The 14th century was the period of the Hundred Years' War, when the French were making constant tip-and-run raids on the Island. The castle was twice captured by the French, in 1373 and 1381. The castle is said to have been captured by a French force led by the Duke of Bourbon in July 1373 in conjunction with an attack on Mont Orgueil by Bertrand du Guesclin. In the account of du Guesclin's raid in 1373 the Duke of Bourbon's standard-bearer reports: "We arrived in Jersey, where there are two castles. The Duke and his men set themselves in array against one and the Constable and his men against the other." It was captured again in 1381, and is thought to become a ruin around the time of the French occupation of Jersey (1461-1468). Local tradition has it that much of the stone was used to enlarge St Ouen's Manor around 1483, and that locals also took down the castle deliberately and used the stones on their own land. It is unlikely the seigneur of St Ouen would have been given such permission if the castle was still in use. On Leland's map of the Channel Islands, published about 1540, it is marked as Grosnes Castrum, dirutum (Grosnez Castle, destroyed). In 1607 the Attorney-General challenged the right of the seigneur of St Ouen to hold his feudal court there, on the grounds that all castles belong to the king; but the Commissioners ruled that, as it was "but a heap of rubbysh and stones", the seigneur might be left in possession.
A ruined fortified circular stone enclosure with a gatehouse, curtain walls and rock cut ditch, with traces of simple buildings to the interior. The granite curtain wall is about 250 metres long and encloses an area roughly circular in shape. The walls are thickest on the landward (S) side - the other sides (N, E & W) being protected by natural steep cliffs some 60 metres high. The most substantial standing structure is the gatehouse, which was protected by a drawbridge and portcullis. There is a portcullis groove descending to passage level, and below the groove is a pit for a counterpoise type drawbridge. Flanking the gatehouse are two D-shaped towers (now reduced to about 2m high). The west tower has remains of two arrow slits at ground level. Between the gatehouse and the east tower is a ramp up to the former wall-walk. There are two other towers further around on the east and west sides, but beyond them the natural defences presumably made flanking towers uneccesary. In front of the gatehouse is a broad ditch cut through the solid rock, originally crossed by the drawbridge. Archaeological excavations of the ditch revealed 12 carved corbels from the gatehouse (now on display at La Hougue Bie Museum). Inside the walls can be traced the foundations of groups of modest structures. (State of Jersey HER)

Links to archaeological and architectural databases, mapping and other online resources

Data >
Maps >
        Where's the path          
Data/Maps > 
Air Photos >
Bing Maps   Google Maps       Flashearth      
Photos >
CastleFacts       Flickr   Panoramio      

Sources of information, references and further reading
Most of the sites or buildings recorded in this web site are NOT open to the public and permission to visit a site must always be sought from the landowner or tenant.
It is an offence to disturb a Scheduled Monument without consent. It is a destruction of everyone's heritage to remove archaeological evidence from ANY site without proper recording and reporting.
Don't use metal detectors on historic sites without authorisation.
The information on this web page may be derived from information compiled by and/or copyright of English Heritage, the various governments of the islands, other organisations and individuals. All the sources given should be consulted to identify the original copyright holder and permission obtained from them before use of the information on this site for commercial purposes.
The author and compiler of Gatehouse does not receive any income from the site and funds it himself. The information within this site is provided freely for educational purposes only.
The bibliography owes much to various bibliographies produced by John Kenyon for the Council for British Archaeology, the Castle Studies Group and others.
Suggestions for finding online and/or hard copies of bibliographical sources can be seen at this link.
Minor archaeological investigations, such as watching brief reports, and some other 'grey' literature is most likely to be held by H.E.R.s but is often poorly referenced and is unlikely to be recorded here, or elsewhere, but some suggestions can be found here.
Please help to make this as useful a resource as possible by contacting Gatehouse if you see errors, can add information or have suggestions for improvements in functality and design.
Help is acknowledged.
This record last updated on Tuesday, April 18, 2017