Roman Empire

This derives from one of a series of marble maps alongside the Via dei Foro Imperio in Rome. Set up in 1912 and now somewhat discoloured and stained, this version has been photoshopped back into something approaching a pristine state (at least within the borders of the Empire). Original labelling is in Italian (Germanico anyone?), so I’ve removed that as well. I like the (authentically) 3D coastline effect and have used it as a basemap (and talking point) in presentations. This purports to show the empire at its greatest extent under Trajan, although the province of Mesopotamia was a very temporary addition. The sites of Kalkreise and Kalefeld (orange) and forts at Laugaricio and Balklava (red) indicate some of the range of earlier and later activity well beyond this border.

The projection appears to be Lambert Conformal, more or less, but my perspective corrections to the upward viewpoint of the original photo have probably distorted this somewhat, so I don’t get a precise fit. Still, most things drop into place pretty well and reprojection (as here to Miller Cylindrical) have an intruiging effect.

Lidar visualisation 2

Taking that last map of slope severity and draping it over a 3D surface model. Some things certainly more evident. I hadn't noticed the hollow way ascending the slope in the bottom left previously; earthworks below the woods in the bottom of the valley; still wonder what to make of the mounds on the far hillside. This produced using SAGA GIS which I'm more impressed with the more I get to grips with its capabilities.

Lidar visualisation

An extract from the Derwent Valley lidar (a pilot study towards the DerwentWISE project). Experimenting with different visualisation techniques. Conventional relief shading, although quite easy to understand, has its downsides in that results can be very dependent on lighting direction. A raft of other techniques has been tried - Sky View Factor, Local Relief Modelling, Insolation Modelling - to varying (but often very good)effect. This plot uses modelling of Slope Severity with pleasing results. I'm particularly interested in the mounds on the hill-top at the north of the image. They don't seem to have been recognised before. Too regular to be natural?

Edmund Artis and Castor

Castor, west of Peterborough, is the site of a substantial ("palatial") Roman structure (or series of structures). Known from the 18th century, they were fairly extensively excavated by Edmund Artis in the 1820s and have been the subject of much work since (if on a rather piecemeal basis). Upex in Britannia 42, 2011 is now the definitive account. This is Artis's plan of the structures investigated by (or just known to) him rectified to fit the modern Ordnance Survey map of the village. Although doubt has been expressed on the accuracy/alignment of some of Artis's structures, the base mapping is impressively accurate. Our own work at the barns near the south-west  corner of the map shows that there is another building range (with hypocaust) here, apparently unseen by Artis (since the barns depicted on his map still stand, it is difficult to imagine he plotted the position of his structure that far out).

Upper Witham Valley 2

This is a slightly wider view of the previous area, again showing the Lincoln edge and low-lying land west towards the River Trent. This time using an (old) bit of GetMapping aerial photography with overlay to pick out some details (inconveniently stopping at the County boundary in the case of the Fosse Way Roman road, I note). Google 'technology evangelist' Ed Parsons reportedly once said he disliked cartographers, “more than anyone in the world”, but I'm afraid I'd have to agree that simply taking a photo of the earth's surface (or a street) isn't the same as creating a map (hence the proliferation of layers and options within google maps over the years). I think the map version actually works better here.

Upper Witham Valley 1

Not really what I would necessarily call the 'Upper' Witham Valley, but following here the terminology of Jolliffe, T. 2010 Archaeology of the Upper Witham Valley, BAR British Series 524, Oxford. One wonders if the title is deliberately obscuring given the (unsuccessful) attempt to keep all site locations secret (an impressive piece of work, this one peculiarity aside). I have always thought the hill-shading on early Ordnance Survey products a much more expressive way of depicting the landscape, even if it lacks the objectivity of contouring. Draping a piece of standard 1:50000 map over a surface model has nice effects where the topography is marked (you can hardly miss the Lincoln edge).

Malawi

Nothing archaeological about this at all (though now I have a base map, all I would need is a list of sites). Our director has spent time working on charity projects in Malawi and the question of availability of mapping came up. Something rather smaller scale was really wanted, but I though I would at least see what I could come up with from SRTM data and other freely available digital sources. The colour scheme may look familiar. I use it a lot (even if it has potential to mislead)!

Chorography and Archaeology

Looks like I just missed this (not that I could have got to Durham on a Wednesday at short notice). Only really chose the blog title as a substitute for something entirely prosaic (Mapping and Archaeology anyone?). Seems there may be an academic discipline about to spring up.

Derwent Valley Lidar

Lidar survey again, and the Derwent Valley again, but somewhat further north than the extract posted earlier, this time at Belper. Same river, different project. Assessing the existing Environment Agency lidar coverage as part of the DerwentWISE Landscape Partnership Project. Nothing much of archaeological interest leaping out so far. The Roman road from Derby (Littlechester) to Buxton is meant to cross the river (east to west) near to the southern edge of this plot, ascending the slope on the west bank (at least according to one theory). I'd like to say the lidar helps prove it one way or the other. Sadly, I can't.