Lemanaghan Bog: the road is rising to meet us

Apr 8, 2022 | Bogs in Transition

The Slí Mór, Pilgrim Path, Lemanaghan Bog; ©KevinO’Dwyer Photography

Introducing Aoife Phelan, the author of this blog post. Aoife is a secondary school teacher of Computer Science and a native of Lemanaghan, Co. Offaly. She is also a member of the Lemanaghan Heritage and Conservation Group. She loves walking, writing and photography and is very interested in local history and the restoration of peatlands. 

Lemanaghan, Co. Offaly, is a place of rich historical importance and has many links to Clonmacnoise. Lemanaghan townsland is located between Ferbane and Ballycumber along the R436. The Conservation Plan for Lemanaghan established that Lemanaghan is:

“A sacred place of great antiquity
A place containing buildings of architectural significance
A place rich in documentary history and archaeological potential
A place where there is a long tradition of devotional practice
A place ‘apart’, possessing a strong sense of being untouched by the modern world”

Above: Image of exposed Sandstone causeway in Lemanaghan Bog, part of the Slí Mor Pilgrim Path, now visible above the bogs surface.

Image Source Left: A Trek through the Bogs, Author(s): Ellen O’Carroll and Jane Whitaker, Source: Archaeology Ireland, Vol. 13,

The ecclesiastical site at Lemanaghan is located on an island of dryland. Lemanaghan island was created by wetlands/bog and the flood plains and callows of the river Brosna. To approach the site from any direction would have required crossing more than 1km of wetlands. A 7th Century church and monastery dedicated to St Manchan is positioned on the dryland, the monastery was founded some time before his death AD664.

Local folklore suggests that Saint Manchan was originally a monk at Clonmacnoise and built a sister monastery in Lemanaghan, he also built a house for his mother Saint Mella. 

This existing stone structure known as Saint Mellas Cell dates to the 10/11th Century. Slí Mór is a Pilgrim’s Road from Ballycumber via Lemanaghan to Clonmacnoise, it tours across the wetland/bog has been used by pilgrims for centuries.

It’s not surprising then, given the significance of the site at Lemanaghan and its connections to Clonmacnoise, that an exceptional number of archaeological finds were discovered in Lemanaghan Bog. Many archaeological discoveries relate to a complex infrastructure of trackways or toghers which were built and repaired over several centuries allowing safe passage across the wetland. The large evidence of toghers in the bog suggests widespread activity in the Lemanaghan area.

Dating evidence suggests that the greatest concentration of track construction coincides with the foundation of the monastery, indicating the importance of the site in the context of the monastic infrastructure of County Offaly.

National Museum Dublin, March 2022.

A significant oak-plank trackway used from 5000 BC was discovered in Lemanaghan. The National Museum is also home to the following items, all found in Lemanaghan Bog; a Neolithic axe head, Neolithic flint scraper, Spearhead, The Wooden Staff — a blackthorn staff discovered adjacent to a medieval trackway, a Bog Body, two different leather shoes, one is post-medieval and the other medieval and a hoard of silver coins. Hence, Lemanaghan Bog is often hailed as one of the highest densities of wetland archaeology in the world giving us a very unique insight into the lives of people over the last 5,500 years.

Image: Front Cover of Lemanaghan Conservation Plan, 2007, The Heritage Council

The fact that two different bishops crosiers were found in Lemanaghan Bog, one of which appears to be the country’s earliest bishop’s crosier and dates from the sixth or seventh century AD. This means that the site was important enough for a bishop to visit. Both of these crosiers are on display in the National Museum Dublin, alongside a replica of Saint Manchans Shrine. The original shrine is a magnificent 12th-century gilt bronze, enamel and yew wood reliquary casket is on display in St. Manchans Church in Boher.

National Museum Dublin, March 2022.

Image Source: Lemanaghan Conservation Plan, 2007, The Heritage Council

In the 1990’s, the Heritage Council commissioned an Environmental Impact Study (EIS) to be carried out along the proposed route of the Pilgrim Path from Ballycumber/Lemanaghan to Clonmacnoise, the results of this study resulted in the Heritage Council and Offaly County Council commissioning a Conservation Plan for the historic complex. The Conservation plan states that “It is important that the options considered for the post-industrial use of the bog are sympathetic to the significance of the site”.

Bord na Móna acquired Lemanaghan Bog in 1949. The bog was utilised for the production of sod peat as fuel, followed by milled peat harvesting for conversion into electricity at Ferbane Power Station and later Shannonbridge Power station. Lemanaghan is connected via bog trains to both Ferbane and Shannonbridge power stations and to Bord na Mona works located at Lough Boora. Locals’ aspirations are for the future of Lemanaghan bog to be in keeping with the conservation plan and highlight the archaeology and the historic character of the area. However, Bord na Mona have proposed a windfarm for the area, this is met with opposition by the local community.

The quantity of disused railways and their connection to existing tourist destinations such as Lough Boora and Clonmacnoise/Shannonbridge, provides potential to create a west Offaly Tourism route. The raised bogs of the Midlands of Ireland appeared after the last Ice Age, around 15,000 years ago. Mesolithic tribes colonised Ireland soon after and one of the most important Mesolithic sites in Ireland is at Lough Boora. Connecting the Mesolothic History of Boora to Early Christen sites such as Lemanaghan and Clonmacnoise has the potential to attract countless numbers of tourists into Offaly, to experience the places of outstanding natural beauty. The disused Clara-Banagher railway line also passes through the townland. It opened in 1884 and closed in 1963. More recent history includes the Castle at Lemanaghan, made famous as it was the place the Annals of Clonmacnoise were translated. In Derryvane Island in the centre of Lemanaghan, there was a safe house and hospital during the war of independence and civil war. The history of Lemanaghan knows no end.

The Archaeological Wetland Unit did extensive excavations in Lemanaghan Bog throughout the years. When they started they would have dug down to find the roadways – with the milling of peat the bog has sunk and the ancient roads are now rising to meet us.

A section of the pilgrim path is now elevated above the bog. The impact that climate conditions are having on the delicate archaeology of the bog needs to be carefully considered and managed. To the right are images of the exposed wooden planks and sandstone in Lemanaghan Bog. This is believed to be part of the Slí Mor, which is recorded as a National Monument. This is our last chance to save the remaining archaeology in Lemanaghan bog.

Above: Exposed wooden planks in Lemanaghan Bog, believed to be part of the Slí Mor Pilgrim Path


BORD NA MÓNA. Bogmen Be Proud: Towards a History of Bord Na Móna, Boora. Offaly: Bord na Móna, Brosna Press, 1997.

OCARROLL, E. (2018). Six Thousand Years of Peatland and Archaeological history in Lemanaghan, Co. Offaly Quaternary of the Irish Midlands, IQUA Field Guide No. 35. Irish Quaternary Association, Dublin.

OCARROLL, E. (2001). The archaeology of Lemanaghan: the story of an Irish bog. [Bray, Co. Wicklow], [Wordwell].

RAFTERY, B; HICKEY, J; (2001). Recent Developments in Wetland Research WARP (Wetland Archaeology Research Project) Occasional Paper 14

THE HERITAGE COUNCIL,(2007), The Lemanaghan Conservation Plan, URL [https://www.offaly.ie/eng/Services/Heritage/Documents/Lemanaghan_Conservation_Plan.pdf]

WHITAKER, J., & O’CARROLL, E. (2009). Peatland excavations 1999-2000: Lemanaghan group of bogs, Co. Offaly. Dublin, Archeological Development Services Ltd.