Heritage Sites of Co. Galway
Cathedral of Our Lady and St Nicholas (RC), Galway
Building of the new cathedral in Galway began in 1957 under the management of contactor John Sisk of Dublin. Architect John Joseph Robinson was responsible for the design of the cathedral, which did not reach completion until after his death. It was built on the site of the old county gaol, which was erected in 1810 but ceased being used in 1939 and was demolished in 1941.
The Byzantine style cathedral, with its magnificent arches and copper dome, was built using local limestone from the nearby quarries. Traditionally the Byzantine style incorporated brick or concrete because there was no suitable building stone available near Constantinople. In contrast, Ireland abounds in superior building stone; Galway city is surrounded by both limestone and granite but limestone was favoured over granite for the cathedral because it is more easily worked and weathers well, exhibiting little discolouration. According to Rev Michael Browne, there was also a biblical reason for choosing stone instead of concrete. In the Office and Mass of the Dedication of a church there is frequent reference to the church as built from living stones. The hymn sings:
The exterior walls are of rusticated ashlar limestone from Anglingham quarry on the shores of Lough corrib. Dark grey in colour, bituminous and fine-grained, this limestone is relatively unfossiliferous and takes a good matt polish to produce a superior black marble. On the surface colonial corals, solitary corals and brachiopods are visible. In thin section the stone contains numerous unicellular foraminifera but little shelly fragments whereas the Merlin Park stone, quarried east of Galway city, contains algae, corals, bryozoans, a variety of foraminifera species, and amorphous opaques. The presence of algae indicates that the lime sediment was deposited in very shallow water.
Strong competitors to the well established Kilkenny black limestone emerged in the early 1800s at Menlough and Anglingham beside Lough Corrib and at Merlin Park close to Galway city, all located on Sir Valentine Blake’s estate. In 1845 it was remarked that the best black ‘marble’ (in fact limestone) quarries in Ireland were on the banks of Lough Corrib. Lower Carboniferous in age, they were deposited in a shallow marine environment 350 million years ago.
The exterior flagstones are from Liscannor in Co. Clare. This micaceous, medium-grained sandstone frequently exhibits Olivellites traces, which form meandering patterns horizontal to bedding, and some parts of the succession contain vertical burrows. The entrance gate pillars are of Ballinasloe limestone from the large and extensively worked quarries at Brackernagh, just southwest of the town of Ballinasloe. This superior, close grained limestone, which can be raised in large blocks, is still actively extracted.
The celebration of Galway stone continues internally with the exposed dark limestone walls and pillars, also from Anglingham. The floor consists mainly of polished Connemara marble from Streamstown (with the exception of the left side chapel, which is from Recess) mixed with Cork red limestone and Portuguese marble tiles.
The most prized stone in the Galway region is Connemara marble. John D’Arcy of Clifden Castle first quarried it in significant volume in the early 1820s and initial exports to London occurred in mid-1824. The quarries were situated at Streamstown Bay, 5 km north of Clifden. Another local landlord, ‘Humanity Dick’ Martin of Ballinahinch (on account of his championing of animal welfare), also extracted the stone from his estate. Much of the marble utilised during the early nineteenth century was obtained from what became the famous ‘Ballinahinch quarries’. stone from this locality supplied the Museum Building of Trinity College Dublin, which was built between 1853 and 1857.
By the late nineteenth century the Ballinahinch quarries, leased by Sibthorpe and Son of Dublin since 1870, were run down due to difficulties relating to transportation and sufficient stone for the market could be raised cheaper at another quarry at Lissoughter, near Recess. In the mid-1890s the leases on the Streamstown and Lissoughter quarries were taken up by Robert C. Fisher, a marble merchant of New York City, and as a result may great New York buildings were embellished with Connemara Marble – most famously the Gould Memorial Library in the Bronx. Throughout the early twentieth century the stone continued to be extracted in moderately limited volume; two notable buildings where it was used are Galway Cathedral and Shannon Airport. It is presently used mainly for the tourist market.
- CAULFIELD, Louise 2019. The Irish marble industry and the Museum Building, pp. 13–51. In CASEY, Christine and WYSE JACKSON, Patrick N. (eds) 2019. The Museum Building of Trinity College Dublin: Setting the standard in design, materials and craftsmanship. Four Courts Press, Dublin.
- FEELY, Martin and COSTANZO, Alessandra 2014. Galway city walks: buildings in Stone. NUI Galway and Galway Civic Trust.
- WYSE JACKSON, Patrick N., CAULFIELD, Louise, FEELY, Martin, JOYCE, Ambrose jr and PARKES, Matthew A. 2020. Connemara Marble, Galway, Ireland: a Global Heritage Stone Resource proposal. Geological Society of London Special Publications 486, 251–268.
Geology of Co. Galway
Galway has some of the most complex geology in the whole of Ireland. Ancient metamorphic rocks such as schist and gneiss (pronounced as ‘nice’) occur through Connemara from Galway City to Inishbofin. The whole of Connemara is a very big structure with massive folds. It is part of the Dalradian sequence that also occurs in North Mayo, Donegal and through into western Scotland. There are even older Precambrian rocks in a very few places exposed by massive faults. Many large areas, such as Connemara, are defined as terranes. These are sequences of rocks that were formed in one place and are now alongside other sequences that were originally formed a long way apart. Major faults in the Earth’s crust have brought them together over millions of years.
The Twelve Bens of Connemara are made of metamorphosed sandstone, which is quartzite. They form hills because they are more resistant to erosion over long periods than the other rocks. Running along the base of the hills are areas of metamorphosed limestone, which is marble. Marble is white if the limestone was pure, but the addition of a few impurities means that the Connemara marble has green bands through it. The Galway Granite is found in south Connemara from Galway City through to Roundstone. It is not one single rock type, but was formed by the intrusion of nine or so large granite masses (called batholiths or plutons) about 400 million years ago. It was formed underground and the molten igneous rock cooled slowly. The rocks that covered it have since been eroded away.
At the same time as the granite was injected below ground, Devonian age rivers were eroding hills and depositing sands and gravels in lower lying areas. Some of these sandstones and conglomerates are seen in Slieve Aughty in the south of the county. Appearing as small inliers, or ‘windows’ to see below these rocks, are Silurian age slaty rocks. Virtually all of Galway east of the city is covered by limestone, deposited in a shallow tropical sea around 330 Ma ago. This has been eroded down over millions of years, since it was formed and then raised to become land. Although it has some caves in it and some karstic features it has not become like the Burren in Clare because in the Ice Ages a thin veneer of sediment was deposited on most of it. So the limestone terrain of east Galway has good soils for grazing with neat fields and limestone walls. In the Aran Islands, the terrain is more like the Burren, with the only evidence of glaciations being some odd boulders of Galway Granite on the bare limestone pavement.
Rocks younger than the Carboniferous are found in only a few tiny patches in Co Galway (not shown on map). A few dolerite dykes, fractures up which volcanic lava moved around 60 Ma ago in the Paleogene (blue on timescale), have been found in the extreme west. Near Headford, pockets of sand and lignite (brown coal) around 3 Ma are preserved in deeply weathered limestone (green on timescale).
Map legend: Geological Map of Limerick (based on GSI 1:1,000,000 map 2003). Pale purple: Precambrian Dalradian rocks; Pale yellow: Precambrian quartzites; Pink: Ordovician; Dark blue: Ordovician igneous & volcanic rocks; Green: Silurian; Red: Granite; Beige: Devonian sandstones and conglomerates; Blue grey: Lower Carboniferous sandstones; Light blue: Lower Carboniferous limestone.