It’s a fantastic site; stuck in the middle of a lake there is an island on which once stood a round house. It is the only crannog that has been found outside Scotland or Ireland. The site itself faced erosion issues which were addressed in the mid 2000s.
It is uncertain whether the original word ‘crannog’ was the name for an artificial island in a waterbody or whether it was the name for the structure built on top. However, in modern language ‘crannog’ is the term used to describe artificial islands created by humans, or sometimes naturally occurring islands within lakes, which are used as platforms for a structure. The structure on top is generally thought to have been an Iron Age-esque roundhouse and evidence of such dwellings dating from as early as the Neolithic period to as late as the 18th century has been unearthed (or unwatered?) by archaeologists since the start of the antiquarian period.
The 10th century crannog at Llangors is the only known example outside Scotland or Ireland and as such has sparked discussions about the connections between Wales, Ireland and Scotland. It has been suggested that our Welsh crannog is a clear indication of Irish – Welsh liaison during that period of history.
The main problem facing the unique site that is Llangors crannog is erosion; natural currents and waves and waves created by passing vessels, have caused erosion of archaeological deposits and deposition of the soils that make up the island. This erosion was effectively moving the island down the lake by removing sediment from one side of the island and then depositing it on the other. In order to combat this destruction a bund was constructed using gabions – a rock wall enclosed by wire mesh – which was designed to stop currents and break any waves before they reached the island thus reducing the erosion.
In order to assess the success of the conservation work undertaken in 2005 it was necessary to take a trip out to the crannog in little rowing boats. We reached the island… eventually… after rowing round and round in circles and ending up closer to the shore than we began (no ‘how many archaeologists’ jokes please).
After the hysterics subsided we took a row around the island to inspect the conservation work; the bund, it seems, is now mostly under water. This could be the effect of raised water levels caused by the very (very) wet weather we have had this year or could have been the result of subsidence of the bund due to soft sediment on the lake floor (or both). However this has happened, the result is that the bund is not working correctly which in turn endangers the stability of the crannog.
So what can we do about this? Well, when (and if) the water levels lower to their normal depth we will be able to investigate further to determine whether the bund has sunk into sediment or whether it is below water purely due to the constant rain and general gloomy weather of 2012. A programme of continuous bund monitoring would allow us to devise methods of bund consolidation to ensure that there is no further degradation of archaeological materials.