GPS: 54.5712 -8.4537
About a 3 and a quarter hour drive from Junction 6 (Blanchardstown) on the M50 – take the M3/N3/A509/N3 to Ballyshannon on Co Donegal (192 Kms). From Ballyshannon, take the N15 north to Donegal, then take the N56 west (towards Killybegs) for a further 40 kms then watch out for the road to St Johns Point, signposted on the left-hand side of the road. St Johns point is approximately 10 kms down this road.
Two excellent shore dives can be accessed from some steps leading to the water near the lighthouse. As these dive sites are on the eastern side of the Peninsula, they will usually be sheltered from prevailing winds and swells. The first (and the more popular) is to Portnagh Rock (A) , the rock is usually (but not always) visible from the shore – getting to takes a few minutes of snorkeling before before dropping down to depths of 25 to 30 meters, lots of rocks, holes, gullies and crevices to explore here and usually plenty of marine life to keep you company. The second dive requires a bit more energy – from the same entry point, snorkel out to the gully between Skuddagh Rock and the mainland – then drop down to circumnavigate the rock before returning to where you started.
The stony sea bed here means visibility will usually be pretty good. The site is sheltered to the west and the north so should be diveable in anything other than a badsoutherly swell.
TIDE, SWELL & WIND FORECAST
Tide, swell and wind forecasts for nearby Rossnowlagh beach are available here
Another shore dive option to consider in this area is Cassin's (Cassan's?) Sound which is about 3kms from the lighthouse as you head back towards Donegal town (GPS: 54.5857,-8.4299).
This dive site faces east and might be more manageable if there is too much swell at the lighthouse. There is convenient parking and easy access to dive site via a slipway, maximum depths here are circa 8m.
The nearest RNLI station is Bundoran (071-9841713), the Irish Coast Guard can be contacted by phoning 999 or 112.
Water temperatures around the north-west coast average around 14c/52f from June to October, varying from lows of around 10f/50c in early June and late October, to highs of 18c/64f or 19c/66f in July and August. Temperatures average around 10c/50f from March to May, varying from lows of down to 8c/46f in early March to highs of up to 15c/59f in late May.
Temperatures average around 10c/50f in wintertime, varying from up to 14c/57f in early November to lows of 7c/44f in January or February.
These are surface temperatures, water temperature 10m down will typically be a couple of degrees lower.