Grosnez Castle

Ruins Ruined medieval coastal castle overlooking dramatic sea cliffs

Ruined medieval castle on Jersey’s northwest headland, reached by coastal paths. Visitors photograph the stone keep and observe sea cliffs and tidal coves from nearby viewpoints.

Main image

Grosnez Castle is a ruined medieval fortification on the northwest coast of Jersey in the Channel Islands, dating to the 14th century. It sits on the headland known as Grosnez Point and is one of the island’s notable coastal ruins.

The site consists of the remains of curtain walls and gateway masonry set on high cliffs with open sea views. People visit primarily for short walks, coastal scenery and photographic viewpoints rather than extensive built fabric.

The castle was constructed in the medieval period as a defensive stronghold and fell into disuse and ruin in following centuries; the surviving masonry is the result of collapse and long-term exposure. Local authorities have carried out basic conservation of the visible walls and gateway to stabilise the remains.

The ruin stands on Grosnez Point in the Parish of St. Ouen on Jersey’s northwest coast, occupying a promontory above the English Channel and coastal cliffs. It lies on the island’s western shoreline and is reached via minor roads and footpaths from nearby villages.

  • Viewing point: Reaches a clifftop position with broad views over the English Channel; best views are from the coastal path north and south of the ruin.
  • Access: Accessible on foot from nearby parking areas and local lanes; paths can be exposed and muddy after rain so wear stout footwear.
Grosnez Castle
Grosnez, Parish of Saint Ouen, Jersey (Channel Islands)
49.2572, -2.2469
Open access (no set hours)
Free

How to Get to Grosnez Castle #

From St. Helier, take the A9 west toward St. Ouen; Grosnez is on the northwest headland of Jersey. By car it’s roughly a 25-30 minute drive (about 16 km) from St. Helier. Local buses (e.g., routes serving St. Ouen) stop in the parish - check Jersey Transport timetables. From the nearest lane, a short coastal footpath leads to the castle ruins.

Tips for Visiting Grosnez Castle #

  • Walk the headland trail clockwise to get sun on the cliffs and better photo light in late afternoon.
  • Bring windproof layers - the headland is exposed and gusts can be severe.
  • Check tide times before clifftop exploring; loose stone and steep drops make footing treacherous.
  • The site has no facilities; nearest toilets and cafes are in nearby Grosnez or St. Ouen.

Best Time to Visit Grosnez Castle #

The headland is best visited in late spring and summer for safer walking conditions and clearer views across the Channel.

Late spring-summer
May-September · 12-20°C
Warmer, drier weather for cliff walks and photography; longest daylight in June and July.
Autumn
October · 8-15°C
Sharper light and fewer day‑visitors; watch for stormy seas.

Weather & Climate near Grosnez Castle #

Climate

Temperate climate with mild summers (peaking in August) and cold winters (coldest in February). Temperatures range from 4°C to 20°C. Moderate rainfall (826 mm/year).

Best Time to Visit
JulyAugustJune
Temperature & Rainfall
Temperature Range
24°
Warmest Month
Coldest Month
Monthly Conditions

January

January is cold with highs of 8°C and lows of 5°C. Regular rainfall (99 mm), mostly overcast skies, and breezy conditions.

40 Poor

Comfort

Feels Like Cold
C
Temperature
83%
Humidity
Very Humid

Weather

99 mm
Rainfall
8.5 m/s
Wind
Breezy
0.1
UV Index
Low
8.5h daylight

February

February is the coolest month with highs of 8°C and lows of 4°C. Moderate rainfall (76 mm), mostly overcast skies, and breezy conditions.

40 Poor

Comfort

Feels Like Cold
C
Temperature
83%
Humidity
Very Humid

Weather

76 mm
Rainfall
7.8 m/s
Wind
Breezy
0.2
UV Index
Low
9.9h daylight

March

March is cold with highs of 10°C and lows of 6°C. Moderate rainfall (73 mm), mostly overcast skies, and breezy conditions.

52 Acceptable

Comfort

Feels Like Cold
C
Temperature
10°
84%
Humidity
Very Humid

Weather

73 mm
Rainfall
7.3 m/s
Wind
Breezy
0.5
UV Index
Low
11.7h daylight

April

April is cold with highs of 11°C and lows of 7°C. Moderate rainfall (46 mm), partly cloudy skies, and breezy conditions.

58 Acceptable

Comfort

Feels Like Cold
C
Temperature
11°
85%
Humidity
Very Humid

Weather

46 mm
Rainfall
6.6 m/s
Wind
Breezy
0.9
UV Index
Moderate
13.6h daylight

May

May is cool with highs of 15°C and lows of 9°C. Moderate rainfall (48 mm) and partly cloudy skies.

62 Good

Comfort

12°
Feels Like Cool
12°C
Temperature
15°
87%
Humidity
Very Humid

Weather

48 mm
Rainfall
5.9 m/s
Wind
Light Breeze
1.3
UV Index
High
15.2h daylight

June

June is cool with highs of 17°C and lows of 12°C. Moderate rainfall (45 mm) and partly cloudy skies.

70 Very Good

Comfort

15°
Feels Like Cool
15°C
Temperature
12° 17°
88%
Humidity
Very Humid

Weather

45 mm
Rainfall
5.6 m/s
Wind
Light Breeze
1.6
UV Index
Very High
16.0h daylight

July

July is cool with highs of 19°C and lows of 14°C. Moderate rainfall (36 mm) and partly cloudy skies.

74 Very Good

Comfort

17°
Feels Like Cool
17°C
Temperature
14° 19°
88%
Humidity
Very Humid

Weather

36 mm
Rainfall
5.6 m/s
Wind
Light Breeze
1.6
UV Index
Very High
15.6h daylight

August

August is cool with highs of 20°C and lows of 14°C. Moderate rainfall (44 mm) and partly cloudy skies.

74 Very Good

Comfort

17°
Feels Like Cool
17°C
Temperature
15° 20°
86%
Humidity
Very Humid

Weather

44 mm
Rainfall
5.5 m/s
Wind
Light Breeze
1.3
UV Index
High
14.2h daylight

September

September is cool with highs of 18°C and lows of 13°C. Moderate rainfall (66 mm), partly cloudy skies, and breezy conditions.

68 Good

Comfort

16°
Feels Like Cool
16°C
Temperature
13° 18°
83%
Humidity
Very Humid

Weather

66 mm
Rainfall
6.3 m/s
Wind
Breezy
0.8
UV Index
Moderate
12.4h daylight

October

October is cool with highs of 15°C and lows of 11°C. Regular rainfall (86 mm), mostly overcast skies, and breezy conditions.

52 Acceptable

Comfort

13°
Feels Like Cool
13°C
Temperature
11° 15°
82%
Humidity
Very Humid

Weather

86 mm
Rainfall
7.5 m/s
Wind
Breezy
0.4
UV Index
Low
10.6h daylight

November

November is cold with highs of 12°C and lows of 8°C. The wettest month with heavy rain (106 mm), mostly overcast skies, and breezy conditions.

48 Poor

Comfort

10°
Feels Like Cold
10°C
Temperature
12°
82%
Humidity
Very Humid

Weather

106 mm
Rainfall
7.9 m/s
Wind
Breezy
0.1
UV Index
Low
8.9h daylight

December

December is cold with highs of 10°C and lows of 6°C. Significant rainfall (101 mm), mostly overcast skies, and breezy conditions.

46 Poor

Comfort

Feels Like Cold
C
Temperature
10°
82%
Humidity
Very Humid

Weather

101 mm
Rainfall
8.4 m/s
Wind
Breezy
0.1
UV Index
Low
8.0h daylight

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