archaeological & built heritage assessment - The Heritage Council

The early Irish medieval period is very much characterized by the long-term establishment of settlement
patterns. Locational factors for such settlements relied on accessibility to transport and communication
which was largely facilitated by the network of lakes and rivers throughout the midlands. The River
Shannon, the most extensive navigable Irish river, played a significant role in this regard. Fording points,
dug-out canoes, and early medieval artefacts found in the riverine and lake environs of the study area is
testimony to this. It is possible that further such evidence is presently contained within the waterway with
deeper waters perhaps housing boat/ship wrecks while intermediate and shallow waters containing items
such as fish traps, landing areas and artefacts such as those listed in Appendix 2.
The late medieval period was an era of castle building in Ireland, and very often those sites located in
strategic positions adjacent to rivers also had associated bridges constructed. Those dating from the early
medieval period would have been built of wood and wicker materials and were regularly burnt during
attacks. However as the later medieval period progressed more permanent stone-built structures were
designed. It is noted from documentary sources that the majority of bridges located within the study area
originated as wooden structures and were later replaced by stone bridges on or near the original location,
such as those at Drumheriff, Leitrim, Jamestown and Cloonavery. It is possible that remnants of these
early bridges survive beneath the water at these locations.
It is noted that dredging works on the Shannon waterways in the past have produced significant quantities
of artefactual material, some of which was found at fording points, which is now housed in the National
Museum of Ireland. The dropping of water levels at Lough Allen has uncovered some interesting areas
where crannógs had been sited off the east shore and as well as other indications of early habitation.
Lough Key is an interesting lake with several small islands and extensive land-based archaeological remains
of medieval date. It is likely that more such remains exist beneath the waters of the lough itself.
Furthermore, the Boyle river is likely to reveal underwater archaeological remains as it serves as one of
the main navigational routes from Lough Key and the Shannon, connecting the historical towns of Carrickon-Shannon
and Boyle.
Underwater sensitive areas within the corridor can be defined as certain fording points (not all of which
have been allocated RMP status e.g. Derrycarne demesne), access points to any of the islands on Lough
Allen, Lough Key or the shoreline, shallow waters forming the Great Loop which surround the peninsula
between Jamestown and Drumsna which is also the location of the Doon, and as a whole the river bed
and deep waters of the corridor are at risk in terms of damage from jet-skis and anchoring respectively.
The speed of boats on Lough Allen, Lough Key, the Carnadoe Waters and the River Shannon has a
negative impact not only on the reed beds surrounding the shores and islands but also on underwater
archaeology. The movement of water can affect and damage fragile features such as wattling (often
associated with crannógs). Furthermore it could expose and dislodge logboats or artefacts which may
originally have been buried in situ or, it could help enhance erosion processes on vulnerable materials and
structures such as quays or landing slips associated with defensive sites.
Any future development of accessibility to the islands of Lough Allen and Lough Key should be welcomed
however an awareness of archaeology and its delicate nature should be made known to those who wish
to gain access to archaeological sites. This could be achieved by the provision of appropriate signage or
information boards. Suitable landing facilities should be made available, provided they do not have an
impact (visual or other) on the monument.
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