North Mains
The site of North Mains is located in Perth and Kinross, in the valley of the River Earn, to the west of Perth. The excavations were undertaken in 1978-9 by Gordon Barclay (see Further Reading for a link to the full article), ahead of the expansion of the Strathallan Aircraft museum runway, and investigated three main sites; a henge, a large barrow, and a pair of ring ditches.

North Mains Henge

North Mains henge consists of a sub-circular ditched enclosure ranging between 32m and 35m in diameter, with the ditches ranging between 2.2-3m in depth and 6-11m in width. The ditched enclosure had two opposing entrances (NNW and SEE), and remnants of an external bank were also identified, which made the monument up to 65m from one side to the other. Within the henge ditch, two rings of postholes were identified; ring B, an oval made up of 17 pits, sat off-centre within the ditches, surrounded by the larger ring A, made up of 24 large postholes, which sat more centrally within the bank and ditch enclosure. The larger ring A postholes had ‘post ramps’ cut into one side of them; this was to allow the insertion of large timber posts into each hole, indicating that ring A, at least, was a timber circle. Interestingly, the post ramps radiated outward from the timber circle, meaning the builders stood outside the ring of postholes to erect the posts when the monument was built. However, these run very close to the inner edge of the enclosure ditch, suggesting that the timber circle was built first, and later enclosed by the bank and ditch enclosure, as it would not have been possible to place the posts within the post ramps if the ditch had already been dug. The pit and post rings and bank and ditch enclosure are accompanied by a total of 16 burials (3 inhumations, 13 cremations) deposited in stone cists, pits, and within ceramic vessels, accompanied by a range of ceramic vessel styles, including Beaker, Collard Urns and Food Vessels. One of these cremations, burial A, was sealed by the henge bank, indicating that at least this burial was deposited before the bank and ditch enclosure was constructed.

Dating North Mains Henge
Existing measurements for this site are primarily on charcoal from postholes within ring A, however, they have large error ranges, and may be impacted by the ‘old wood effect’ (where heartwood charcoal from long-living tree species, such as oak, return radiocarbon measurements that are too old). Three measurements on cremation burials indicate these date to the 22nd-19th century, which, in the case of burial A under the henge bank, also provides the earliest possible date that the bank and ditch enclosure was built. Project Time aims to identify further samples from the as-yet undated burials at the site, to understand the character and timing of mortuary practices, and select osseous samples from the timber circle, to produce a clearer chronology of the sites development and use.
North Mains Barrow
North Mains barrow is a very large mound, 40m in diameter, and 5.5m in height. Excavation revealed a complex construction; it began (Phase IIIA) with a central posthole, with shallow gullies radiating away from the post to the east, south and west. Around this central post, a broadly circular post-built enclosure, approximately 7m in diameter, was built, which in turn had a series of fence lines radiating outward from it. Eight were identified at this phase of construction, but more fence lines were added as construction went on. The next phase of construction (IIIB) saw a circular ditch dug around the fence lines, with the material being dumped in the ‘bays’ between the fences, and some material also being deposited in the central circular enclosure. By the end of this phase, the monument took the form of a ‘ring bank’, with material deposited up against the central enclosure fence line, forming a bank c.20m wide from peak to peak, and between 0.5 and 1.4m high. The end of Phase IIIB was marked by the deposition of small boulders in all of the bays, from the top of the bank down onto the inner slope of the bank. Following this, more material from the ditch was deposited in phase IIIC, again within the bays, some of which showed evidence of the fences being extended upwards as the barrow grew larger. Material was also deposited into the central area, but this was distinctly different, being made up mainly of stone. This phase ended with the deposition of turf within the bays, and across the central area, which still existed as a hollow in the top of the mound. Following this, phase IIID was represented by a layer of ashy material within the central hollow; this indicated activity including fires, however, earlier disturbance of the mound top meant it was not possible to get a clear understanding of this. The hollow was then fully filled in phase IIIE, and the whole barrow was finally covered with cobbles in phase IIIF, apart from the central area, 14-15m in diameter, which was capped with larger slabs.
The mound had a total of 10 burials within it; six of these (two inhumations and four cremations) were deposited into stone line cists and pits after the turf covering was added at the end of phase IIIC, including two that were accompanied by complete food vessels. Three of these cremation burials contained the remains of multiple individuals, including the remains of adults and children. During the final cobble covering of the barrow another multiple individual cremation burial was incorporated into the mound within a stone lined cist, and a final cremation burial in a cist was added to the barrow after the cobble covering of phase IIIF.
Dating North Mains Barrow
There are only three radiocarbon measurements from the North Mains Barrow; all three are on charcoal and have large error ranges (and potentially impacted by old wood effect). Project Time aims to identify suitable samples from the burials to provide measurements for deposits throughout the sequence of the barrow construction. The project will also aim to select multiple samples from those burials with multiple individuals in (selecting the same skeletal element to ensure our samples are from different individuals), to investigate whether these deposits are made up of individuals cremated at the same time, or individuals cremated at different times, which were then curated and kept, before being deposited together at North Mains (for a discussion of similar practices of mortuary manipulation and curation, read Tom Booth and Jo Bruck’s recent paper on this topic).
Further reading
Barclay, G., Barnetson, L.P.D., Bohncke, S., Collins, G., Cowie, T.G., Denston, C.B., Hulme, P., Kenworthy, M., Lunt, D., Pare, C. and Powers, R., 1984, November. Sites of the third millennium bc to the first millennium ad at North Mains, Strathallan, Perthshire. In Proceedings of the Society of Antiquaries of Scotland (Vol. 113, pp. 122-281). Available here (http://journals.socantscot.org/index.php/psas/article/view/9120)