Return to the ‘Cromlech Tumulus’ – a Bronze Age roundhouse on Slievemore

Return to the ‘Cromlech Tumulus’ – a Bronze Age roundhouse on Slievemore

It’s been a busy few weeks here on Achill. In July we bade farewell our pre-Famine settlement at Keem Bay and made the move to the slopes of Slievemore mountain to the site of the ‘Cromlech Tumulus’. Despite what the name suggests the site is in fact a large Middle Bronze Age roundhouse. Slievemore was a rather busy place in the second millennium BC. Our current site is the third MBA roundhouse to have been excavated on Slievemore and it forms part of a much broader prehistoric landscape encompassing a web of pre-bog field walls and a series of megalithic tombs. Our project at the ‘Cromlech Tumulus’ has been ongoing since 2014. The site was marked on the RMP as a ‘megalithic structure’. For over 175 years scholars argued over what the site actually was. Some maintained that it represented a ‘sepulchral complex’ while others dismissed it as a series of more recent huts. Our excavations  have determined that the site is in fact a very substantial Middle Bronze Age roundhouse with three later huts built on top.

Excavations 20142016

During our three seasons of excavation we have opened five large trenches over the site covering an area of some 12m by 16m. The first two seasons concentrated on the western end of the site, uncovering the thick earth-and-stone walls of the roundhouse, and the dense concentration of pits and postholes dotting the building’s floor. Many of these features undoubtedly relate to the timber frame that carried the roundhouse’s roof, or served as storage pits. Two of the pits had ‘odd’ contents that marked them out—the first held a pebble carved to resemble a face as well as half a broken quern rubbing stone, and the second held cremated bone, possibly human. These special deposits are likely to be magic or votive offerings designed to protect the dwelling or to mark important points in the lifecycle of the building or its inhabitants (as argued by scholars like Kerri Cleary and Joanna Bruck). To the south of the cutting overlying the roundhouse we found an late-medieval hut site that was dated to 1435 -1618 AD using charcoal from its hearth.

Plan of the ‘Cromlech Tumulus’ roundhouse. This year’s trench is at the east of the roundhouse.



In 2016 we opened a new large trench—5.5m by 10m—along the eastern side of the site. This trench (Quadrant 5) focused on an important part of the monument, investigating the area where the entrance was likely to be located. It also included the remains of a dry-stone clochán hut peeking out from the peat—it is likely to be post-medieval in date. Quadrant 5 contained some fascinating EBA features, chief of which was a curved east-facing entrance channel lined with stones. We also identified part of a pre-bog field wall running up to meet the roundhouse in this trench. Unfortunately we ran out of time before this important area could be fully investigated in 2016.

2017—What we’ve found so far

We’re back in Quadrant 5 this year—picking up where we left off. Our priority for 2017 has been tacking the eastern wall of the roundhouse. We want to trace it in our trench and find out how it relates to the entrance passage and the pre-bog wall (‘Danish Ditch’) that runs into the eastern side of our cutting. Our first steps were removing last year’s back-fill and cleaning the whole trench down so that we could see what was going on. The area where we think the roundhouse wall is is covered in a thick layer of soil and rubble which we’ve been taking down methodically to reveal the earlier structure beneath. In the south of the trench work is ongoing uncovering the extent of the pre-bog field wall. One of the richest areas of the site so far has been a deep sondage (small trench) in the north-east corner of our trench. The sondage cuts through a stony bank flanking the northern wall of our entrance. We found a layer full of worked stone and charcoal under the stone, hinting at a pre-house phase of activity!

Our director Eve has been digging a very deep hole! We found a nice cache of lithics at the bottom indicating a possible pre-EBA house phase.

This year we’ve been using a lot of photogrammetry to record our trenches. The model below shows the northern half of this year’s trench. You can see the curved entrance channel in the north of the trench, and the pre-bog wall entering from the east in the south of the trench.