Portmuck Harbour is situated on the northeast coast of Ireland to the east of Larne Lough and on the seaward side of the Islandmagee peninsula. Tucked into the peninsula, to the northwest end of the Isle of Muck, it offers a small harbour with an anchorage immediately offshore and the opportunity to dry out alongside its pier.

The little bay provides a tolerable anchorage with shelter and protection from southeast through south to west in winds up to Beauford 4 to 5. Although there are no off-lying dangers, and the bay can be accessed at all stages of the tide, attentive navigation is required for access. Rocks extending from the pierhead and the opposite shore require good visibility and keen observation whilst anchoring.

As Larne’s High-Speed Sea Services ferry lifts and drops off the plane a bow wash can roll a great distance into the bay. Boats at anchor here should be prepared for an occasional short sharp wave.

Keyfacts for Portmuck

Position and approaches

Haven position

54° 50.878' N, 005° 43.673' W

This is the position of Portmuck’s pierhead.

What is the initial fix?

This is located 400 metres north of the bay outside of Portmuck’s pier. A course of due south for 200 metres along Islandmagee shore leads into the anchoring area that is the small bay north of the car park.

What are the key points of the approach?

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What's the story here?

Portmuck is a pretty harbour located on the northwest coastline of Islandmagee. It is situated close inside a small coastal islet called the Isle of Muck. The Isle of Muck is located 300 metres off the mainland, which, despite its name, is not an island as it is connected to the shore by a narrow drying ridge of stones and boulders. The small harbour is fronted by a little bay and has a 25-metre-long stone pier with a boat slip.




The small bay provides an anchorage with good holding. The pier at Portmuck dries out beyond the pierhead at low water springs. However, a vessel can find as much as 3.5 metres at High Water Springs against the wall. So vessels that can take to the bottom may dry out alongside over sand with some stones.

How to get in?

Offshore details for vessels approaching Strangford Lough from the north are available in northeast Ireland’s coastal overview for Malin Head to Strangford Lough . The 37-metre-high Isle of Muck located a ⅓ of a mile eastward of the anchorage will be clearly seen from all approaches. The high and bare green island presents a perpendicular sea-facing cliff to the east.




Vessels following the coastline from Larne should take care to stand off the northernmost point of Islandmagee, Skernaghan Point. Skernaghan Point, which translates to 'Point of the Reef', has a rocky outcrop that stretches northward from it that has been responsible for numerous shipwrecks. It should be given a berth of at least 500 metres.




On rounding Skernaghan Point, continue southeastward for 1½ miles alongside Islandmagee’s precipitous cliffs that range in height from 15 to 31 metres. This coastline is clear of obstructions and a distance of 150 metres out from the rocks or holding to the 10-metre contour or deeper clears all dangers.




Vessels approaching from the south have no outlying dangers as deepwater will be found close in under the cliffs. Black Head lighthouse, 5 miles southward of the Isle of Muck and situated on the northern extremity of Belfast Lough, makes a conspicuous closing sea mark.

Black Head Lighthouse - Fl 3s 45m 27M position: 54° 46.016’N, 005° 41.338’W

To the north of Black Head, the coast of Islandmagee presents a steep perpendicular cliff composed of black basaltic rocks. At The Gobbins, commencing 2½ miles southward of the Isle of Muck, this attains a height of 45 metres.




The preferred approach is to round the Isle of Muck keeping at least 400 metres off the northernmost stacks of the island, and then to turn in towards the initial fix. It is possible for shallow draft vessels to pass between the islet and Islandmagee shore at high water. The island is attached to the shore by a narrow neck of shingle beach that exposes at low water.



However, this narrow connecting ridge can be covered by as much as 2 metres at high water springs. But this is not always the case and it can vary according to barometric pressure and wind direction. As such the cut between the islet and shore has many variables and the draft needs to be moderate or small. Hence the recommended approach is to round the island on the outside.





The Portmuck Initial Fix sets up a northern approach into the bay. Located 300 metres northwest of Portmuck’s pierhead, just inside the 4-metre contour, it takes a southern approaching vessel well clear of the exposed reef and hidden rocks that extend 150 metres northward from the harbour’s pierhead.




Steering a course of due south for 200 metres along the Islandmagee shore leads into the anchoring area.




Anchor in the small bay approximately 200 metres north of the car park with the slip open of the head of the pier. Good sand holding will be found here in 5 metres.


The harbour is entirely exposed to anything from the north. However, it is possible to achieve some measure of protection from these conditions by anchoring in 3.5 metres to the south of the drying ridge that connects Muck Island to Islandmagee. The northerly protection available here is limited and in such conditions, a vessel would be best advised to head the short distance south to Carrickfergus or the anchorages along the north shore of Belfast Lough.

Why visit here?

Portmuck derives its name from 'Muck Isle' or 'Isle of Muck' itself a direct translation from the Gaelic 'Inis Muc'. 'Muc' means 'pig' in Irish and Inis means 'islet'. It is believed the island acquired its name from its earlier inhabitants by appearing to resemble the shape of a sleeping pig.




The peninsula's name, 'Islandmagee', on which the harbour is situated, hails from the Portmuck area. The name is directly derived from the Gaelic 'Oileán MhicAodha' meaning 'MacAodha's island'. The Gaelic MacAodha clan, who owned and controlled the peninsula, had their home at Portmuck. From their time right up to today the little bay of Portmuck has been adapted to play many roles throughout history. Portmuck hosted at various times a monastery, a fortress and the present harbour was specifically built to facilitate the industrial role of Islandmagee limestone for export in the latter 1820s.




At the time it was owned by William McClelland who lived above it. McClelland was a radical who led the Islandmagee United Irishmen when they rebelled against the authorities in 1798. After it failed, he had to flee with a price on his head. He later returned under amnesty and lived the remainder of his life at Portmuck. He was a renowned smuggler and it was this illicit trade that the government concluded was the real reason he invested in the pier. In response to this, they built coastguard cottages and a revenue station in his farmyard, still present today, to keep an eye on proceedings which put pay to any smuggling. The trade in cut stone continued regardless but fell into terminal decline by the 1920s. By the end of the decade, the harbour went into ruins.





In the 1980s government grants were made available to support local fishing activity from small locations such as this. If a number of fishermen were dependent on a pier in question, central government funds would be made available for renovation. Remarkably the isolated Portmuck had the requisite number and the restoration work took place creating the beautiful small harbour that exists there today. It is often lamented that the many long-since deceased fishermen whose names bolstered the application's numbers could not enjoy the fine harbour they brought about.




The adjacent Muck Island, despite its name, is technically not an island. Although located 300 metres off the mainland an ever-shifting ridge maintains a connection to Islandmagee. This dries at low water springs and is scarcely covered at neaps when it is technically passable for a short period to walk out to the island over a mixed sand and shingle bar. However, it is today home to the third largest cliff-nesting seabird colony in Northern Ireland and it is looked after by the Ulster Wildlife Trust. As such the island has been designated a bird sanctuary and no unauthorised public access is permitted. Likewise, it is dangerous, as at high water springs it has up to two metres of cover and the currents run fast here. So this would never be the place to go exploring and get the tides wrong.




The island itself lies north to south and has an overall length of about 1,000 metres, and has three small rocky stacks off the northern end. Its height increases from west to east presenting attractive steep 30-metre-high basalt sea cliffs to seaward. The combination of the east-facing cliffs and coastal grasses in the central part of the island provides an attractive mixture of wilderness habitats for a wide variety of seabirds. The nature reserve is the home of Kittiwake, Razorbill, Black Guillemot and Guillemot who all breed here.




Today the small harbour of Portmuck is partly silted and the focus of leisure pursuits for the community and beyond, with a picnic area and cliff-top walks offering views across the Irish Sea out to Scotland. It was designated an Area of Special Scientific Interest (ASSI) for its beauty and the variety of wildlife it hosted. In 2003 the National Trust acquired the strip of coast, for a mile or so on either side of the harbour. They set in place a northern and southern linear trail to enable visitors to engage and enjoy the dramatic views and coastal scenery over the Isle of Muck from Islandmagee. The terrain for both paths is mostly grassy with occasional uneven rocky surfaces, steps, swing gates and stiles throughout the walks.




The northern route is accessed from the car park across the picnic area; go through the wooden swing gate, turn left and follow the path up the slope to the cliff top. The National Trust walk is bounded by private land that is well marked, so return by the same route. This path offers a particularly attractive opportunity to photograph a vessel at anchor. Here the cliff provides an elevation of almost 40 metres to shoot a vessel anchored off the harbour or between Islandmagee with Muck Island situated in the backdrop. Both have the southern sun behind and the elements of cliffs and the Irish Sea out beyond and Scotland just visible, to make for a spectacular photo opportunity of a vessel at anchor.




The southern route may be accessed by ascending the steps beside the harbour. Follow the path to the rocky shore and continue to where the low water ridge over to the Isle of Muck exposes itself, then follow the trail up the slope to the right. Then follow the main grassy path for about a half mile to the end. Return by retracing your steps or take another trail that leads to a minor road that leads back to the harbour car park. This route provides spectacular views of Muck Island from the adjacent shoreline and the cliffs above it from the south.




From a coastal cruising point of view, Portmuck is the hidden gem that is too often overlooked along this coast. It offers an excellent stop-off point for northbound or southbound vessels making their way along the coast. It also provides an ideal point of departure or arrival for the Western Isles of Scotland. It is non-tidal, free from off-lying dangers and access is immediate and straightforward from seaward. It also serves as a highly convenient tide wait location to allow mariners to take full advantage of favourable tidal streams that are the dominant feature of this area of the coast, not to mention its highly useful half-tide eddy to the north of the island. Those who drop in here will be treated to a stunning little harbour that provides access to a beautiful coastline within a few strides out from the pierhead.

What facilities are available?

Toilet blocks are available on the pier and the harbour has a good slip. Contact the harbour master, who could not be more helpful, for any resources required including basic Marine engineering that may be available locally.

The small village of Mullaghboy, one mile away, has basic provisions to service its population of about 300 people and a café that serves good food. Almost everything else is available at nearby Larne harbour.

Any security concerns?

Never a problem known to have occurred in Portmuck Harbour.

With thanks to:

Terence Stitt, Portmuck Harbour Master. Photography with thanks to KyleH, Wilson Adams, Albert Bridge, Mary and Angus Hogg, Eskling, Aubrey Dale and Mike Simms.