Grosnez Castle

Grosnez Castle is a ruined 14th-century castle in Saint Ouen, situated in Grosnez in the north-west corner of the island of Jersey in the Channel Islands. Philippe de Carteret held it against the French when they held half of Jersey between 1461 and 1467, but it has been a ruin since the mid-16th century,

Today, the ruins are open to the public. Furthermore, there are concrete steps that lead from the rear of Grosnez Castle to a small automated signal station; the station platform affords scenic views.

Name
The name comes from the old Norse words for "grey headland" - grar nes - an accurate description of the site when seen from the sea. In time the spelling evolved to resemble the French for big nose. A nearby headland to the west has a similar name, Rouge Nez.

History
Sir John des Roches ordered the castle built around 1330, about the time of the start of the Hundred Years' War. The castle's purpose was to provide local farmers with a place of refugee from French attacks.

The walls are of local granite and are thickest on the landward side. The castle's position on a clifftop 200 ft (~ 60 m) above the sea means that the natural features of the site protect it on three sides. A ditch dug into the rock provides protection on the fourth side. The remains of ruined walls, mostly footings, are still present.

A drawbridge and portcullis protected the gatehouse, which is the only substantial surviving remnant, and would have made it difficult to capture. There are traces of six simple buildings. The castle, though, had a number of weaknesses:
 * There were no sally ports for counter-attacks;
 * Most importantly, there was no water well inside the walls.

The French captured the castle in 1373 and 1381. The castle was probably demolished around the time of the French occupation of Jersey (1461–1468). In 1483 the Seigneur of St Ouen was allowed to fortify his manor house and it is unlikely he would have been given permission if Grosnez was still in use.

In 1806, a naval signal station was established at Grosnez to send messages to Guernsey.

Modern depiction
Grosnez Castle appears on the reverse of the Jersey 50 pence coin.