Trackways and Boats

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TRACKWAYS AND BOATS

Throughout prehistory humans negotiated access through their environment via structures such as trackways and roads and through the use of a range of boats in riverine, estuarine, and coastal contexts. Evidence supports the hypothesis that prehistoric populations had the ability to cross significant water bodies, such as the North Sea.

TRACKWAYS

From northern Europe alone—in Britain and Ireland, the Netherlands, Denmark, and northern Germany—roughly one thousand trackways and roads have been discovered, primarily through exposure during commercial and private peat-cutting activities. Perhaps one of the more famous, and certainly most intensively studied, trackways recovered to date is the Sweet Track found in the Somerset Levels, a large expanse of peat land in Somerset County, southwest England. The Somerset Levels is a low-lying area on the southern side of the Severn Estuary. Fieldwork has been carried out in the Somerset Levels since the nineteenth century, but the formation of the Somerset Levels project in 1973 under the direction of John Coles and Bryony Coles enabled systematic surveying and recording of the wetland archaeology of the Levels. The Sweet Track ran for a distance of about 2 kilometers from the base of the Poldern Hills on the south side of the Levels in a northeasterly direction to a sand island called Westhay.

One of the most important aspects of waterlogged archaeology is that waterlogging excludes oxygen from the burial environment, making it anaerobic and thereby inhibiting the activities of bacteria and fungi—key agents in the decay process. Waterlogging preserves a wide range of materials, resulting in the recovery of significant organic evidence for past human activities. The Sweet Track is an excellent example of the preservation afforded by waterlogging. It was discovered during peat cutting in 1970 by Ray Sweet, after whom it was named. This trackway is a single-plank walkway constructed across the reed and sedge beds of the Levels. Environmental evidence collected during excavation and sampling—in particular, the specific environmental preferences of the beetle species whose remains were recovered from the peats in which the trackway was preserved—indicates that in certain areas the trackway crossed pools and areas of open water.

The trackway was constructed using split oak trees to produce planks of about 3.4 meters long and 0.6 meters wide. Pegs of hazel and alder were used to secure poles of ash, alder, hazel, or elm that formed the substructure of the track, with the pegs hammered in obliquely to produce a secure base for the plank walkway. Over the basal structure thus produced, peat and vegetation were deposited to provide further support for the upper planks. These planks were made of oak, set down parallel to the basal poles and wedged in place between the tops of the pegs. Finally, the planks themselves were occasionally secured in place by vertical pegs driven through holes that were cut toward the ends of the planks. The excavations carried out along the trackway showed that it followed the line of an earlier trackway, called the Post Track, which was constructed of long planks of ash and lime laid on the marsh surface and marked by posts of hazel spaced at 3-meter intervals along its route.

The excellent preservation of the Sweet and Post Tracks has provided significant insights into the woodworking capabilities of prehistoric populations. Numerous finds have been recovered in close proximity to the trackway since its initial discovery by Ray Sweet, who himself found a Neolithic "leafshaped" arrowhead when he found the first ash plank of the trackway. Other finds include numerous flint artifacts including an unused flint axe. A particularly important discovery was of a jadeite axe, a polished light green stone, which was in perfect condition. The significance of this axe is that its source is the foothills of the European Alps, indicating long-distance exchange networks that would presumably have required transport across the North Sea or English Channel. The precise dating of the trackway, afforded by dendrochronological (tree-ring) analysis of the oak planks, indicates that this axe found its way to southwest England in 3806 or 3807 b.c., the year the trees were felled. This precise calendar age provides a context for other finds along the trackway, including a broken pot with its contents of hazelnuts, a wooden dish, and several leaf-shaped arrowheads. One of these arrowheads retained the resin used to secure it to its shaft, whereas another retained a part of the shaft and evidence for its binding.

The Sweet Track is just one of many trackways found in the Somerset Levels, but in 2003 it was the earliest yet known. Other forms of trackway continued to be constructed across the Levels into the later prehistoric periods up to c. 500 b.c.

In Ireland, systematic survey and excavation undertaken by the Irish Archaeological Wetland Unit has recovered more than one thousand prehistoric sites in the wetlands of County Longford, County Mayo, and County Offaly. Many of these sites are trackways, called toghers in Ireland, and given that there are about 1.2 million hectares of wetland in Ireland, the need for routes across the bogs is readily apparent. Trackways of all periods from c. 3650 b.c. to a.d. 1450, except for a hiatus at c. a.d. 1–500, had been recovered from the Irish bogs as of the early 2000s.

One such site is Curraghmore-16 in County Offaly, a single-planked oak walkway 580 meters long, which is estimated to have been built c. 1625–1435 b.c. on the basis of radiocarbon dating. In a fashion resembling the construction of the Sweet Track, the Curraghmore planks were secured by pegs driven through mortise holes cut in their ends. The distinguishing feature of Curraghmore-16's construction is the extreme narrowness of the planks; at about 0.2 meters wide, they are among the narrowest in a single-plank walkway ever discovered in Ireland.

In the Mountdillon Bogs of County Longford, Ireland, the opposite end of the chronological range of planked trackways is found. The planked corduroy road of Corlea-1, first studied scientifically in 1984, is the first known Iron Age trackway from the Irish wetlands. Dendrochronological analysis dates this trackway at 148 b.c. Corlea-1 is made from oak sleepers about 3 or 4 meters long (on average), placed side by side over longitudinal roundwood rails, or runners, of oak. Numerous wooden artifacts were recovered from under the track's timbers: these finds included parts of a wagon, pieces of buckets, handles, and a piece of timber with markings comprising lines thought to represent the earliest evidence for writing in Ireland.

Trackway finds and associated artifacts constructed in wood provide significant insight into the woodworking capabilities of prehistoric and historic communities. Past communities split oaks to produce planks and managed woodland to ensure sustainable timber supplies. Woodland management also assured the provision of roundwood poles for use in the making of "hurdles," woven wooden panels used in another form of trackways and similar to fencing panels still in use today in some areas. The presence of mortise holes and reused structural timbers of buildings found in some trackways also provide insight into possible woodworking practices used in prehistoric house construction.

boats

Throughout prehistory humans used water-borne transport to facilitate movement in their landscape. Such craft included hide boats, sewn-plank boats, and dugout or logboats. In the Stone Age fjords of Halsskov and Lindholm, Denmark, at least 21 Mesolithic boats have been excavated. In total, some 250 logboats have been recovered from Denmark, 57 of which date to the Stone Age. The Mesolithic boats are found in coastal contexts and are dated to 5400–3900 b.c. The excavated evidence, supported by experimental studies, indicates that the Danish logboats were made by hollowing out tree trunks with an axe, a technique considered quicker and more controlled than the use of fire. The boats were constructed from linden trees and were about 6 or 7 meters long; their hulls were between 1 and 4 centimeters thick. A finished boat had a pointed bow and a stern with a separate bulkhead. Such logboats would probably have been capable of crossing large expanses of sea, allowing their navigators to travel between 20 and 40 kilometers from the mainland.

One of the most significant forms of prehistoric boats are the Bronze Age sewn-plank boats recovered from the Humber Estuary on the east coast of England, from the Welsh side of the Severn Estuary, and from Dover in southeastern England. These craft attest an advanced level of technological skill in boatbuilding beginning c. 2000 b.c. Experimental studies have shown that these craft would have the potential for crossing the North Sea and could possibly have been propelled by sail as well as by paddling. The finds from Ferriby on the Humber Estuary in Yorkshire have been interpreted by their original finder, Edward V. Wright, as being from a boatyard or similar facility. The original find of a Ferriby boat was made in 1937. A half-scale reconstruction of Ferriby 1, a sewn-plank boat dated to 1880–1680 b.c., was undertaken in 2003 (fig. 1). The maximum length of boat discovered in the Humber is about 16 meters. The keel plank was curved upward at the bow and stern, and the side planks were tied in to the keel. An unusual aspect of these craft was the use of stitches to hold the planks together. Finds of planking and aspects of the construction identified from the study of these timbers have shown that between 2000 and 1600 b.c. these craft would have been substantial; the boats themselves would have weighed about 4 tons empty, and they were able to carry a cargo of 7 tons or about thirty passengers.

The sewn-plank boats from England all reflect an advanced level of construction technique, suggesting that the original construction and development of these craft may date back to the very earliest part of the Bronze Age, at c. 2500–2000 b.c. Their social and economic context would thus coincide with the rise in importance of the individual, a shift from the Neolithic emphasis on communal societies. The fact that variations occur in Britain during the Neolithic is significant in that the Yorkshire region of England has individual burials from c. 3000 b.c. Individuals were buried with "prestige" items thought to reflect the status or importance of the individual who was buried. Many of the prestige items were traded from the Continent, arriving in Britain in a manner probably similar to the circumstances that brought the jadeite axe found at the Sweet Track. The development of prestige exchange networks in the Bronze Age and possibly the later Neolithic may reasonably be associated with the sort of boats found at Ferriby and elsewhere in Britain. Furthermore, the Yorkshire region is a known source of jet, a black stone that was polished and used to make necklaces, buttons, and other items. Objects made from jet are found throughout the British Isles in burial contexts associated with "important" individuals, from the Neolithic into the Bronze Age between c. 3000–1600 b.c., signifying that long distance trade in Whitby jet is synchronous with the rising importance of the individual in British prehistory.

The Humber Estuary was also the site of a significant logboat discovery: a craft 12.78 meters long and 1.4 meters wide, constructed from a single oak tree that was felled between 320 and 277 b.c., was recovered from the wetlands adjacent to the Humber. Excavation has shown that this Iron Age vessel, known as the Hasholme boat, may have been carrying a cargo of meat, and in the absence of evidence to the contrary, it is usually assumed that this craft was used for the transport of cargo in riverine contexts. The size of the single oak tree from which the Hasholme logboat was constructed suggests that oak forests still existed in the British landscape into the Iron Age period. Environmental evidence from the Humber region has suggested that the area to the north of the Humber may have been heavily forested throughout the Bronze Age, when the Ferriby boats were constructed, and remained wooded into the Iron Age.

Prehistoric populations around the world exhibit advanced woodworking capabilities from early times. Trackways and watercraft attest a considerable level of technical expertise, using techniques that are still in use in the twenty-first century. The need to cross watery areas such as bogs and rivers or seas is stimulated by the everyday requirements of access to resources such as the plants, birds, and animals in the wetlands of the Somerset Levels. The movement of cargo, as in the case of Hasholme, where meat may have been transported, or the Ferriby craft, which may have been integral to the Early Bronze Age exchange networks that were a fundamental part of society at that time, was equally important throughout both the prehistoric and the historic periods around the world.

See alsoBoats and Boatbuilding (vol. 2, part 7).