Muglins Sound is located between the small Dalkey Island and a separate cluster of rocks with a light tower called The Muglins. Both lie off Sorrento Point the southern extremity of Dublin Bay.
Sorrento Point, Dalkey Island, Muglins Rock and Kish as seen from Killiney HillImage: Passps via ASA 4.0
Passing through Muglins Sound, or Dalkey Sound, cuts about 1 mile off a typical passage between Killiney and Dublin bays. The sequence of description is from south to north.
Why sail this route?
There are three main ways for a northbound vessel to enter the southern side of Dublin Bay. Or, conversely, for a southbound vessel to connect with the inshore passage which is the preferred route as far as Wicklow.- (i) Pass between Dalkey Island and the mainland via Dalkey Island Sound.
- (ii) Pass between Dalkey Island and the Muglins via Muglins Sound.
- (iii) Pass outside the Muglins, offshore and in open water.
The Dalkey Sound
is the preferred fairway and the one normally used by leisure craft. But when the tidal current are adverse, Dalkey Sound's funnelled streams are the most challenging and small craft are best advised to go outside and use Muglins Sound or take the offshore route. 
Muglins seen behind St Begnet Church on Dalkey IslandImage: William Murphy via CC BY-SA 2.0
The much more straightforward offshore route, detailed in the Dublin Bay to Rosslare
Coastal Description, is the best approach for a newcomer to take at night, with poor visibility or in uncomfortable weather. But in reasonable conditions with good visibility, passing between Dalkey Island and the Muglins via Muglins Sound is the preferred adverse tide approach.Tidal overview
Today's summary tidal overview for this route as of Sunday, December 3rd at 07:59. Muglins Sound and further offshore the tides turn half an hour later than in Dalkey Sound. The north going stream begins at Dover -0530, (HW Dublin -0600). The south going stream begins at Dover +0030 (HW Dublin HW).Southbound
(HW Dover +0030 to +0642)
Now
(Tidal flow )
Ends in 01:10:49
(Sun 02:58 to 09:10)
Northbound
(HW Dover -0530 to +0042) 
Starts in 01:23:49
(Sun 09:23 to 15:35)
What are the navigational notes?
Muglins Sound is situated in the ¼ of a mile wide channel that lies between Dalkey Island and a small cluster of rocks called The Muglins.
Dalkey Island and The Muglins as seen from the southPhoto: jnestorius cc BY-SA 3.0
The small Dalkey Island is 24 metres high and 600 metres long with a Martello tower on its summit. It lies immediately offshore 200 metres to the east of the mainland leading down to Sorrento Point and about two and a half miles southeast of Dún Laoghaire Harbour.
MuglinsImage: Michael Harpur
Muglins is a different group or chain of rocks. It is 6 metres high and bold-to except to the westward, where for 100 metres distance there is a rock with 1 metre of cover. There is a lighthouse on The Muglins, that could more aptly be described as a distinctive beacon, making it highly recognisable. It is a white conical tower with a red band:
The Muglins - Lighthouse Fl 5s 9m 11M position: 53° 16.524’N, 006° 04.579’W
The ¼ of a mile distance between Dalkey Island and the Muglins is named the Muglins Sound. The navigable channel, between the outlying dangers on each side, is about 300 metres wide.
The complete course is 0.64 miles from the waypoint 'Southern approach' to 'East of Leac Buidhe Rock' tending in a north north westerly direction (reciprocal south south easterly).
Southern approach, 53° 16.060' N, 006° 4.514' W
A ⅓ of a mile southeastward of the Martello Tower on Dalkey Island.
► Next waypoint: 0.43 miles, course ⇓ 339.81°T (reciprocal ⇑ 159.81°T)
Muglins Sound, 53° 16.460' N, 006° 4.760' W
This is about midway between Dalkey Island and Muglins.
► Next waypoint: 0.21 miles, course ⇓ 327.73°T (reciprocal ⇑ 147.73°T)
East of Leac Buidhe Rock, 53° 16.640' N, 006° 4.950' W
250 metres east of the covered Leac Buidhe Rock that dries to 0.2 metres.
Navigating through the Muglins Sound is straightforward as the channel is 300 metres wide with a general depth of 15 metres, with the exception of and one small area of 6.4 metres.
To go between Dalkey Island and the Muglins, keep slightly to The Muglins side of mid-channel. Remaining outside the 10-metre contour, deeper, and adjusted for the tide, will avoid all dangers.
Yacht approaching Muglins Sound from the northPhoto: Tourism Ireland
Muglins is bold-to with clear water all around, except for one rock, with 0.8 of a metre LAT of cover, that lies about 100 metres to the west of the light. Below half tide most leisure craft should keep 200 metres out from Muglins in order to avoid this rock.
The dangers of Muglins Sound are predominantly on the Dalkey Island sideImage: Michael Harpur
Most of the dangers are however on the Dalkey Island side of the sound and the reef that extends northward from Dalkey island that terminates in Maiden Rock with straggling outliers on both sides of it.
The foul are that extends northward of Dalkey Island Image: Tourism Ireland
The principal danger is the mostly covered Leac Buidhe which barely dries at low water. It is situated approximately ¼ of a mile north of Dalkey Island and 200 metres southeastward of Clare Rock that stands about 600 metres northwest of Dalkey Island. Keep at least 200 metres off the northeast side of Dalkey Island, and off Clare Rock will avoid the dangers on the island side of the sound, including Leac Buidhe.
Passing south of Muglins SoundPhoto: Tourism Ireland
A simple rules of thumb for Muglins Sound is that a northbound vessel, not using the provided waypoints, may avoid Leac Buidhe by progressing due north through the middle of the sound until Maiden Rock is abeam. Likewise, a southbound vessel should steer for mid-channel on a bearing of due south, maintaining depths of greater than 10 metres of water, until Muglins is abeam before turning off southeastward.
What is the best sailing time?
Sailing season for Ireland is May to September, with June and July offering some of the best weather. Nevertheless the incidence of winds up to force seven and above in June and July are on average two days each month. So you may be either held up or having a blast depending on your sailing preferences. Ireland is not subject to persistent fog – statistically complete days of persistent fog occur less than once in a decade.With thanks to:
eOceanic
