Stack Rocks Island

Stack Rocks is a small island a mere 500 yards off the southern side of St Brides Bay, where the coast turns south-west towards the little beach at St Brides Haven.

Due north of Mill Haven, the geologist would see it simply as a pyramidal chunk of Pre-Cambrian igneous rock sticking out of the sea, which would have been a tor on the landscape before the sea levels rose millennia ago. On the nearby mainland cliffs are other examples of glacial geology, including the junction of the Pre-Cambrian with the Old Red Sandstone at the northern end of the Iron Age Fort overlooking Mill Haven and Foxes Holes. This border is clearly marked by a change in the colour of the surface of the coastal footpath from red to brown. Looking north-east the hard, irregular Pre-Cambrians rise high above the flat-topped Old Red Sandstone, with rocks dominating the landscape, Stack Rocks being one of the most prominent. And further down on the southern side of inaccessible Warey Haven cove are grey igneous blocks protruding from the clifftop, which are classic examples of ‘glacial head’ caused by the melting ice of a huge glacier. Nearby is a fine-grained grey, near-granite block split in two and dropped from the ice, another example of glacial action.

To the present-day walker along the National Park Coastal Footpath, which traverses the entire 170-mile coastal circuit of Pembrokeshire from St Dogmaels in the north to Amroth on the Carmarthenshire border, Stack Rocks are simply another picturesque feature to be seen along the way. With a crown of gale-contorted gorse and a few tufts of thrift and sea campion it is quite colourful in spring time, when it is also occupied by a few cliff-nesting seabirds. There is usually the odd cormorant around, fishing in the deep water beneath the cliffs, and the occasional seal peeping above the surface at the passer-by on the footpath.

The locals like to fish around the Stack, some as a leisure time activity when there are mackerel and seabass about, others as a means of income, for lobster and crab thrive on the rocky seabed in the Bay.

Few people go ashore on the Stack, for there is no water there and no shelter, but a few years ago two intrepid local men, one of them a National Park Warden, decided to see how long they could survive there. They lasted a week or so before their water bottles ran dry. Little wonder, then, that there is no evidence of habitation; no promontory fort and no legend of Celtic monk or saint.

Apart from the wildlife, the only company nowadays would be the supertankers which use this side of the Bay as an anchorage as they await the availability of a berth on one of the terminals along the shores of Milford Haven Waterway. There are often up to seven or eight large vessels riding there.

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