Heritage Sites of Co. Monaghan

Courthouse, Church Square, Monaghan

Monaghan courthouse was built between 1827 and 1830 to plans designed by Joseph Welland. The renowned Victorian ecclesiastical architect was responsible for the design of over 100 Church of Ireland churches throughout Ireland until his death in 1860; the courthouse in Monaghan was one of his earlier projects. A neo-classical design, the edifice was erected on the site of the old gaol; the builder was Thomas Stewart and it cost £10000. A new gaol was built between 1814 and 1824 on High Street, which was later adapted as a county infirmary and eventually demolished and replaced by the current Monaghan County Hospital in 1932-38.

The entrance façade of the Courthouse exhibits channeled rustication on the ground floor and a Doric portico with a pediment bearing the royal coat of arms of the United Kingdom, intricately carved in Portland Stone. The building was constructed using large ashlar blocks of biscuit-coloured sandstone sourced from Eshnaglogh mountain quarry in Co. Monaghan, situated 15 km north-west of Monaghan town. This medium grained, greyish cream coloured stone is the Carnmore Sandstone Member of the Meenymore Formation and it is Mississippian (Carboniferous) in age. Some of the stone for the courthouse may also have been sourced from Donagh in Co. Monaghan, a quarry located 4.5 km from Monaghan that also supplied ornamental stone for the quoins and other external decoration in the Roman Catholic Cathedral.

The courthouse came under attack during the Civil War and bullet holes are still visible on some of the columns. In 1981 the building was destroyed by fire and remained vacant until its reconstruction in 1986. Refurbishment of the courthouse took place during the first decade of the twenty first century and by 2011 the façade had been restored to its original state. The twentieth century extension was removed from the front of the building; the stone was cleaned; and Carnmore sandstone from Rossmore Quarry in Fermanagh was used for repairs. The Fermanagh stone used in the refurbishment is from the same bed as the Eshnaglogh stone used originally in the construction of the building.

The OPW Architectural Services were responsible for the refurbishment and John Sisk and Sons Ltd. was the main contractor. In 2012 this restoration venture was acknowledged with an Irish Architecture Award under the category of Best Conservation/Restoration Project.

Further reading:

Geology of Co. Monaghan

With the exception of the southern slopes of Slieve Beagh, in the extreme north-west of the county, the landscape of Monaghan is low and gently undulating. The oldest rocks form a strip from north-east to south-west across the centre of the county. These Ordovician rocks, around 460 to 445 million years old, consist mostly of mudstone and muddy sandstones, or ‘greywackes’, but include some submarine lavas. They accumulated on the floor of an ocean at a depth of more than 4000 metres. Similar dark mudstones and greywackes of Silurian age, around 445 to 440 million years old, again with some minor submarine volcanics, form a much broader band across much of the southern half of the county.

The northern third of the county is underlain by Carboniferous rocks, from around 360 to 330 million years old. They are very poorly exposed but boreholes show that the earlier rocks are pebble beds and sandstones, overlain by limestones and then by thick mudstones and sandstones on the south slopes of Slieve Beagh. The pebble beds at the base were deposited in broad shallow rivers, which were gradually submerged, as sea level rose, by lagoons and then by shallow tropical seas represented by the limestones. The younger mudstones and sandstones above them were deposited by river deltas encroaching into the sea as sea level was falling again.

Carboniferous and younger rocks, surrounded by much older Silurian rocks, are found in the extreme south-east of the county where they have subsided along a major tectonic fault. Grey Carboniferous limestone, deposited on a shallow sea floor around 330 million years old, are overlain by younger Carboniferous sandstones and mudstones with a few thin coal seams, deposited in an Equatorial swamp or delta environment around 320 million years ago.

Strikingly different rocks lie above and to the west of these Carboniferous rocks. Red mudstones with two gypsum beds, up to 35 metres thick, are Permian in age, around 255 million years old, while thick red siltstones and sandstones above them are Triassic, slightly less than 250 million years old. Both the Permian and Triassic rocks accumulated on a desert land surface, with gypsum being deposited as saline lakes dried out under the arid conditions.

The youngest rocks in the county lie above, and within, these Permian and Triassic ‘red beds’. Basalt lavas lie above the Permian gypsum, being quarried at Knocknacran, while dykes and sills, the fissures up which the lava travelled to reach the surface, have been seen both in the opencast gypsum pit and in the underground mine. These lavas are almost certainly of Paleogene age, around 60 million years old, a time when much of north-eastern Ireland was wracked by volcanic activity.

The ice sheets that covered Co. Monaghan during the last Ice Age have had a profound influence on its present landscape. Most of the low ground is thickly blanketed with glacial till, or ‘boulder clay’, obscuring the bedrock geology beneath. Over much of the county this was moulded by the moving ice sheet into the countless drumlins, which give the landscape its ‘basket-of-eggs’ appearance.

Map legend: Geological Map of Limerick (based on GSI 1:1,000,000 map 2003). Pink: Ordovician sediments; Grey green: Ordovician & Silurian; Dark blue: Lower Carboniferous sandstones; Pale blue: Lower Carboniferous limestone; Dark green: Upper Carboniferous shales; Brown: Triassic sandstones.