by Graham Robb
Medionemeton is now Bar Hill, where the suburbs of Glasgow give way to the Campsie Fells. A path leads through scraggly woodland to the earthworks and some moss-carpeted footings. No one knows why a small Roman fort on the edge of the civilized world bore such an evocative Celtic name. A ‘nemeton’ was a sanctuary. There are still about forty place names, most of them in Britain and France, which contain the time-worn phonemes of the word.14 ‘Nemeton’ may have been related to the Greek ‘nemos’ (‘wood’), because the Celts – so the poet Lucan claimed – made their sanctuaries in sunless groves where the trees dripped with the blood of human sacrifice, and ‘altars horrible on massive stones upreared’. A more likely origin is the word ‘nem’ – also found in Old Breton and Old Irish – which means ‘sky’. This would make a ‘nemeton’ a ‘celestial place’ and ‘Medionemeton’ a near-synonym of ‘Mediolanum’. A nemeton was a template of the upper world, a portion of the heavens mapped out on the earth, just as a Roman templum was a space marked out either in the sky or on the ground for the purpose of taking auspices (here).
Apart from the sacred name and the crows in the oak trees, the mysteries of Celtic religion are entirely absent from the Bar Hill fort. The only divine presence unearthed there is a small sandstone altar dedicated to the Roman god Silvanus by the grateful prefect of a cohort of Syrian archers. Perhaps the shrine from which the altar came already existed when the foreign troops arrived with their trenching tools and soil baskets, but there is no evidence of Celtic deities, let alone an ‘altar horrible on massive stones upreared’. The ‘medio’ has proved just as baffling as it is in ‘Mediolanum’: Bar Hill is not in the ‘middle’ of the Antonine Wall; there are twelve forts to the west of it, and eleven to the east; it lies two Roman miles closer to the western terminus than to the eastern. Yet here, on the edge of the Roman empire, the riddle is expressed as the simplest of all designs – a straight line.
The Roman method of planning roads and frontier walls consisted, very roughly, of this. Two terminal points were chosen – in this case, Bishopton, across what was then the fordable Firth of Clyde, and Carriden, ten kilometres west of the Forth Road Bridge. An imaginary line was drawn between the two termini and traced on the ground by a process of triangulation or some other form of geometrical alignment.15 Sometimes, the finished road would follow the straight line of the survey. Often, because of a pre-existing route or an obstacle – a marsh, a ravine, a hill too steep for horses – it would deviate from the line, but rarely more than a few Roman miles. The Antonine Wall is a typical example of the art: with the survey line drawn on a map, it resembles a vine entwining itself around a stake. No fort on the Antonine Wall is more than 2.6 kilometres from the survey line, and for its entire length there are conveniently low hills from which the surveyors could take their bearings.
The operation can be recreated on a computer in less time than it takes to lug a dioptra, a sundial and a bundle of wooden posts to the top of a hill. Something that was known to the original surveyors in AD 142 becomes immediately apparent: the line passes through the shrine at Medionemeton – not just nearby, but bisecting it exactly. This ‘middle sanctuary’, which occupies one of the highest areas of ground between the two terminal points, was the prime coordinate on a long-distance line and the central pivot of the northern frontier.
9. Forts of the Antonine Wall
The difference is negligible if the western terminus of the Antonine Wall is taken (as it often is) to be the fort of Old Kilpatrick on the Firth of Clyde, or if Medionemeton is identified with Croy Hill, the eastern neighbour of Bar Hill.
To the legionaries who stood guard on the empire’s edge, the name ‘Medionemeton’ probably meant very little. Under the windblown beacon, with the black-faced sheep huddled up against the hedges, the sacred geography of a barbarian race would have been a matter of total indifference to a Syrian archer. He was there because Emperor Antoninus had ordered a wall to be built between civilization and the wild tribes of the north. But he was there, too, because a shrine had stood on that spot in days gone by, and because the wall itself, like Hadrian’s Wall to the south, followed a route that was already ancient and patrolled by a god more powerful than the imported rustic Silvanus.
Though the Scottish Medionemeton has only now given up its secret, the surveying sense of ‘medio’ is neither eccentric nor particularly mysterious. Every ancient survey was based on the association of measurement with a mid-point. A ‘meridian’ (from ‘medius’ and ‘dies’) is a line drawn in the direction of the sun’s shadow (due north) at the mid-point of its daily course. True midday occurs when the sun lies due south, which is why the ‘Midi’ is the South of France.
10. ‘Midday Mountains’ as boundary markers
Throughout the Alps and the Pyrenees, for example, there are ‘Midday Mountains’ (Mittaghorn, Pic du Midi, Punta del Mezzodi, etc.), which are usually said to have indicated, from the point of view of the people who named them, the position of the sun at midday. These convenient peaks are supposed to have been gigantic gnomons on snow-covered sundials. In fact, most of the Midday Mountains are useless as chronometers. A straightforward experiment shows that their practical function was quite different. Plotted on a map, they turn out to mark boundary-lines and frontiers, some of which are at least as old as the Roman empire. Like Medionemeton, these ‘midday’ points are the surveying poles of territorial divisions that were probably first established in the late Iron Age.
Since many of the commonest place names date back to the Iron Age, it seemed quite possible, when I began to pursue this endless path that led everywhere and nowhere, that these and hundreds of other ‘middle’ places – some on high ground, others on slopes that scarcely deserve to be called ‘hills’ – once belonged to the same local networks as the Mediolana.
11. Mediolana and ‘mid hills’ in Picardy
Distances are in kilometres, to the nearest hundred metres. ‘Vallée Millon’ and ‘Le Milanet’, on the right of the diagram, may be derived from ‘Mediolanum’. They were discovered simply by following the pattern. Coincidentally, perhaps, aerial photographs of the field called ‘Le Milanet’ – a site unknown to archaeologists – appear to show rectangular ditches or enclosures.
This was not a theory to be tested lightly. In the Middle Ages – which is when most place names were first recorded – there were hundreds of montes medii in western Europe. I eventually located almost one thousand ‘mid hills’ from northern Scotland to the eastern Alps. Some of them occur in the same region as Mediolana and seem to form local groups of ‘middle’ places. A few had even been Mediolana themselves until the old Celtic name was conflated with the more familiar ‘mons medius’.
When the curiously fascinating operation of finding and plotting every middle place was complete, something quite intriguing appeared. In some regions, where enough place names have survived, even at a distance of more than two and a half thousand years, the patterns are strikingly consistent. Without the Gaulish place names, this map of Mediolana and other ‘middle places’ in Picardy (fig. 11) would look like one of the triangulation charts produced by the Cassini map-making expeditions of the eighteenth century.
This cartographic pattern deduced from early Iron Age sites may be the oldest detectable sign of large-scale territorial organization in northern Europe. Apart from the stone tablets in the museum of Orange on which roads and rivers are etched across the gridlines of a Roman survey – and ignoring the dubious chiselled stone from ‘Caesar’s Camp’ at Mauchamp on the river Aisne which happens to resemble an outline of France – nothing like a modern map has emerged from the ancient world. But on this evidence, the information needed to create a map existed.
Perhaps the science of long-distance measuring had travelled along the trade routes that opened up at the end of the Hallstatt period, bringing the Aegean to within a few weeks of northern Gaul. Something of Hellenic civilization had already reached the Mediterranean coast of Gaul a generation before Massalia was
founded by Phocaean traders. In 650 BC, the natives of Agatha (Agde) were acquiring Greek ideas along with Greek wine and ceramics. When they aligned their necropolis on the rising sun of the summer solstice, they were following a native Bronze Age tradition, but when they divided it up into regular allotments, they used a Greek unit of measurement.
Compared to the precise centuriations of Mediterranean towns, the Mediolanum system in the north of Gaul is patchy and incomplete. The similar distances suggest that an ancestor of the Gaulish leuca (‘league’) was already in use, though, like most units of measurement until the twentieth century, it would have varied from one region to the next. The whole system might even be attributed to chance, were it not for the fact that its regularity is quite distinct from the patterning effects of catchment areas and supply zones. Sanctuaries and hill forts tend to be more or less evenly dispersed: each population required a certain acreage of arable and woodland, and a reasonably convenient centre. Like the five oppida shown in the map above (here), which follow the winding course of the river Somme, they usually occur along natural routes. The ‘middle places’, by contrast, suggest a deliberate application of geodetic science to the landscape.
The urge to map and organize a territory is not completely unexpected in a culture that excelled in the amicable division of land. The inter-tribal roads of the Gauls and their high-speed telegraph system could hardly have been devised without long-distance surveys that would have taken many years to evolve. Nor is it surprising that Celtic tribes wanted to impose an administrative and sacred order on the natural chaos of hills and rivers and on the vagaries of human habitation. Earlier societies had written on the landscape with alignments of ditches and stones. The gigantic prehistoric hieroglyphs of Carnac, Stonehenge and Avebury were known to the Celts. But the organization of middle places implies a collective project almost too ambitious to be credible: it would mean that only a generation or two after a recognizably Celtic civilization arose, the Celts were attempting to survey and measure regions that spanned many tribal territories.
For some time after this ghostly remnant of an ancient map came to light, I thought that the coordinated group of Mediolana in what was later the territory of the Ambiani must be an isolated phenomenon. Only in a few areas do all the other Mediolana and the hundreds of other ‘middle’ mounds and hills form such coherent patterns. Perhaps only a few local networks ever existed, or perhaps the evidence has vanished beyond recall. The map of Mediolana and middle places presented here (fig. 12) lay on my desk for several weeks as an inscrutable curiosity: was this the threadbare remnant of a continent-sized tapestry of networks or a monument to wasted time? And yet, the map as a whole was strangely eloquent. The concentrations of ‘mid hills’ are unexpectedly independent of topography: in some of the hilliest regions, there are none at all, while some barely undulating landscapes are full of them. Two lines seem to run from the region of the lower Rhone: one follows the trajectory of the Via Heraklea; another, more ragged line runs up the valley of the river Isère into southern Switzerland. There is no obvious correlation with tribal or linguistic zones, and yet there is a pattern, which an archaeologist might recognize at a glance.
The scatter of ‘middle places’ looks remarkably like a map illustrating the early spread of Celtic civilization from the eighth to the fifth centuries BC. The concentration in the eastern Alps and the middle Danube would correspond to the proto-Celtic Hallstatt culture, which is named after the salt mines of a lakeside settlement south-east of Salzburg. The warrior aristocrats of the Hallstatt owed their wealth to the prehistoric salt routes that joined the European Plain to the Adriatic and the Mediterranean. An unrecorded catastrophe caused the collapse of the Hallstatt aristocracy. With the founding of the Greek trading port of Massalia, new markets opened up, and the rivers Rhone and Saône became important corridors of trade. The centres of power shifted to the west and the north, and to the culture known as La Tène – from an archaeological site on Lake Neuchâtel. This is the culture that produced the characteristic mazy swirls of Celtic art. In Gaul, its main focus was the Marne, though there were also signs of cosmopolitan luxury further south, in the town that was known to the Romans as Avaricum (Bourges).
One of the richest burials of this first period of Celtic expansion is the treasure-filled tomb of the princess of Vix. It lies in a region where a concentration of middle hills begins to fan out towards the Rhineland and the Channel ports. It is not immediately apparent why – five centuries before the planting of the first Gaulish vineyards – a hill in Burgundy should have been the home of such a fabulously wealthy woman, nor, for that matter, why Alesia, the ‘mother-city’ of the Gauls, should be in the same region. Today, it would be obvious only to a tourist planning a long-distance barge holiday. Vix and Alesia stand at one of the busiest commercial crossroads of the Celtic world: this is the principal watershed zone of western Europe, where merchants coming from north and south unloaded their oak-plank boats and met on the overland route that joined the Rhone–Saône corridor to the broad and gentle rivers running to the English Channel and the North Sea.
12. ‘Montes medii’ and Mediolana in Europe
From maps, title deeds, topographical dictionaries and various other texts. In France alone, after two thousand years of linguistic change, the term ‘medio’ takes exactly one hundred different forms, or if the various words for ‘hill’ and ‘mountain’ are included, two hundred and eight. Many names will have disappeared before they could be recorded, but the map gives a reasonable impression of the original distribution. The complete list can be found at www.panmacmillan.com/theancientpaths, with latitude and longitude coordinates to four decimal places. This pinpoints the location to within 9.5 and 10 metres, depending on latitude.
Like many apparently banal place names, ‘medio’ is a slippery term. In its earliest forms, it occurs most frequently with the word ‘mons’, meaning ‘hill’ or ‘mountain’. A ‘Mid Hill’, a ‘Maiden Hill’ a ‘Meall Meadhonach’, a ‘Mittelberg’ or a ‘Montemezzo’ can be a hill that lies between two others, a hill of middling height, an upland area where animals are pastured between the lower slopes and the peaks, or a hill shared by two communities; in Britain, it can also be a corruption of ‘mickle’ or ‘muckle’, meaning ‘very large’. Often, however, its origin is obscure, and toponymists are unable to account for it. In such cases, the Celtic survey provides an explanation.
The areas of the map that are either blank or only sparsely covered with ‘mid hills’ and Mediolana reflect the population patterns of pre-Roman Europe. At this early stage, not all of western Europe was Celtic. The cultural divisions noted by Greek and Roman writers are broadly confirmed by the archaeological record: Ligurians on the coast to the east of Marseille, Etruscans in northern Italy, Germanic tribes in the north-east, and Iberians in the south-west, especially south of the Heraklean diagonal (figs 1 and 3). In Gaul itself, the Atlantic west was a separate zone: relatively few metal objects from the late Bronze Age have been discovered there, and most of those are isolated finds, dissociated from any settlement or cemetery. In south-western Gaul, the river Garonne, which looks like such a useful shortcut from the Mediterranean to the Ocean that it often appears on speculative historical maps as a major trade route, was practically deserted. The reasons are not entirely clear. Perhaps the prehistoric tribes of the Atlantic coast retained a firmer hold there than elsewhere, or perhaps the Celts were reluctant to colonize the last, watery realms before the land of the dead. Even as recently as the nineteenth century, Brittany and the Cotentin Peninsula, the marshes of Vendée and Poitou, and the trackless scrubland of the Landes were culturally and economically separate from the rest of France. The first Celtic settlers probably discovered what ethnologists and administrators found there in the nineteenth century – a stunted, malarial population, clinging feebly to the edge of the inhabited world.
These survey-points of the early Iron Age, and the obscure tales they tell, are certainly Celtic, but they
come from an age when the tribes inhabited their own small worlds, each one probably no larger than the pays of pre-industrial France. The glorious precision of the Heraklean Way belonged to a relatively cosmopolitan part of Gaul: on the shores of the Mediterranean, where Iron Age hill forts look out over oil refineries and towering cruise-ship cities bound for the Aegean, sophistication of this order still seems quite credible. Further north, on the puddly flats at the foot of Mont Lassois near the hamlet of Vix, there are only a few reminders of a cosmopolitan past – the stickiness of spilled grapes on the tarmac in September and the migrant pickers from what was once the Carthaginian empire. Most foreign visitors follow the same routes as Iron Age traders; they come from the Channel ports and the Low Countries along the ‘Route des Anglais’ and the ‘Route des Hollandais’, bringing euros instead of tin and amber, on roads that pass through the northernmost zones of middle mountains.
In rural Burgundy, the protohistoric scene is easy to picture: the maze of hazel hurdles, the granaries on stilts, the sagging, mossy thatch. But if the ancient settlement could be recreated and explored, there would after all be evidence of incongruous inventions and outlandish technology: there, among the hedges and the barns, would be the glowing laboratory of the metallurgist, his threads of gold and his carbon-steel blades, the delicate anvils and directed heating-jets, and all the modern instruments of his magic.