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 short cut 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.

Photo: Arnout Vos 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 Saturday, January 16th at 23:12. 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 04:09:41
(Sun 03:22 to 09:47)
North Going Stream
(HW Dover -0415 to +0145) Now
(Tidal flow )
Ends in 04:09:41
(Sat 21:22 to 03:22)
What are the navigational notes?
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)
Dursey Sound - Northern Entrance, 51° 36.933' N, 010° 9.840' W
This is a quarter of a mile north-westward of the cut on the 50-metre contour.