This route provides guidance waypoints to assist navigation through the coastal cut provided by Dursey Sound. Dursey Sound is a deep but narrow channel between Dursey Island and the southwestern extremity of the Beara Peninsula, that is bounded to the north by the Kenmare River and south by Bantry Bay.
Why sail this route?
Dursey Sound offers sailors a shortcut to and from the Kenmare River and Bantry Bay. With a least charted depth of 11.6 metres CD, Dursey Sound is deep but it has a tidal race and the fairway is reduced to a width of about 70 metres by covered rocks that extend out from the mainland side.However, it saves at least an hour of sailing and makes for an interesting passage. It also avoids the complications of navigating a path through The Bull, The Cow and The Calf rocks that lie to the west of Dursey Island of which only the Bull Rock is lighted.

Image: ArnoutVos via CC BY-SA 2.0
This is not a foul-weather cut as both ends of Dursey Sound are exposed to the Atlantic Ocean and a large seaway can be encountered in the sound itself. This is further complicated by shifting and funnelling wind-over-tide.
Tidal overview
Today's summary tidal overview for this route as of Wednesday, February 12th at 13:01. Tidal streams in the sound are strong attaining 4kn in the narrows where it sets in line with the fairway. The main east going stream enters the north entrance of Dursey Sound at Dover +0145 (Cobh -0450) and then turns southward. The main west going stream enters the southern entrance at Dover -0415 (Cobh +0135) and then turns northward. The fairway’s strong tidal streams create eddies in the approaches and can cause overfalls in the narrows.As such it is advisable to make a transit with a favourable tide or at least before it reaches its maximum rate.
South Going Stream
(HW Dover +0145 to -0415)

Starts in 00:06:50
(Wed 13:08 to 19:33)
North Going Stream
(HW Dover -0415 to +0145) Now
(Tidal flow )
Ends in 00:06:50
(Wed 07:08 to 13:08)
What are the navigational notes?


Image: Colin Park via CC BY-SA 2.0
Dursey Island is located 1½ miles west-northwest of Crow Head. The island is 250 metres high, 3½ miles long and is readily identified by an old signal tower on its summit. Dursey Sound lies on the east side of the island between it and the southwestern end of the mainland’s Berra Peninsula.
The tidal stream in the sound attains 4kn in the narrows so this will be the primary determinant of the timing for the passage. A settled conditions tide wait location for northbound vessels may be had Dursey Sound Anchorage

Image: Allie Caulfield via CC BY-SA 2.0
A cable car, with a vertical clearance of 24 to 21 metres, descending westward toward the island, spans Dursey Sound’s narrows and a ferry crosses the sound 300 metres to the southeast of the path of the cable car. An overhead telephone cable, with a vertical clearance of 25 meters, passes over the sound close north of the cable car.

Image: Tourism Ireland
Those planning a southern approach should make note of a couple of rocks that lie off Crow Head the southwest corner of the Berra Peninsula. The drying Cat Rock is located about 400 metres southwest of the extremity of the head and is very much in the way of vessels moving between Bantry Bay and Dursey Sound.

Image: Graham Rabbits
It dries to 3.3 metres and generally makes itself known by its breakers. The Bull’s Forehead rock, awash and 300 metres west of Crow Island, should also be avoided.
The complete course is 2.89 miles from the waypoint 'Dursey Sound - Southern Entrance' to 'Dursey Sound - Northern Entrance' tending in a north north easterly direction (reciprocal south south westerly).
Dursey Sound - Southern Entrance, 51° 34.643' N, 010° 11.455' W
This is 1 mile west of the dangerous Cat Rock towards which both tidal streams set. Proceed northeastward from here making certain not to be pushed toward the Bull's Forehead rock, situated close west of Crow Island and 600 metres northwest of Cat Rock.
► Next waypoint: 1.81 miles, course ⇓ 43.84°T (reciprocal ⇑ 223.84°T)
Between Illanebeg and the Old Breaker, 51° 35.950' N, 010° 9.434' W
This is about midway between Old Breaker and Illanebeg the southwest entrance point of the sound.
► Next waypoint: 0.41 miles, course ⇓ 9.73°T (reciprocal ⇑ 189.73°T)
Crossing the ferry route, 51° 36.352' N, 010° 9.323' W
This is in about 10 metres of water closing in upon the Dursey Island side of the fairway. It crosses the first of two routes that the ferries typically take to the island.
► Next waypoint: 0.13 miles, course ⇓ 345.78°T (reciprocal ⇑ 165.78°T)
Midway between Flag Rock and the Dursey Island, 51° 36.477' N, 010° 9.374' W
This is the narrowest part of the fairway, on its southwestern side, between Flag Rock and Dursey Island. It is about 60 metres south-eastward of where the cable car spans the narrows.
► Next waypoint: 0.54 miles, course ⇓ 327.61°T (reciprocal ⇑ 147.61°T)