Roman Military Base with Wooden Obstacles

[Adrian Nayler]

Members interested in Romans and their fortifications may like to note this important paper from 2020, available here:

https://journals.ub.uni-heidelberg.de/index.php/ak/article/view/82366

"A Roman Military Base with Wooden Obstacles of Approach.
Preliminary Report on the 2019 Excavations on the Blskopf« near Bad Ems (Rhein-Lahn-Kreis)
Excavations on the Blskopf« near Bad Ems on the River Lahn yielded a Roman military installation of about 0.1 ha in size of the Claudio-Neronian period. In the inner V-shaped ditch pointed timbers in the style of an obstacle of approach were proven for the first time in situ and in an excellent state of preservation. In analogy to the pila muralia, these are called pila fossata«, a term hitherto not recorded. The military installation formed part of a linear ditch-and-rampart system and probably served as a barrier in the terrain. An area of mine shafts and finds of slag from Roman contexts indicate a connection with mining activities. The proof of a Roman date for these mine shafts is still lacking."

Do not be put off by the German text; all the pictures are in English! (See especially pages 531 and 533)

[Imperial Dave]

nice find and report Adrian!

[vexillia]

This might help ...

[Adrian Nayler]

My German is pretty non-existent but I don't think that the illustration highlighted by Martin, taken from the article, is of the site in question. It seems rather to show the opposite of the new find. The illustration seemingly has the stakes 'planted' atop the watch-tower's defensive banks. The site in question found the stakes, fitted into a beam, seated at the base of a v-shaped defensive ditch.

[vexillia]

I did say "might". 

[Imperial Dave]

This might help ...

fantastic representation, for once the sudes correctly illustrated!

[Erpingham]

My German is pretty non-existent but I don't think that the illustration highlighted by Martin, taken from the article, is of the site in question.

No, its not.  It is actually an outpost watch tower on the Kapellenberg.  The article is about a Limes fort on the Blöskopf.  The bank and ditch of the Limes runs down the east side of the fort.

[Adrian Nayler]

Since my initial posting, I have managed to run the article through Google Translate. The downloadable pdf is an archive file which needs converting to a 'regular' pdf before Google Translate will work (it took me some time to realise this). Though machine translation is not perfect, especially with technical papers, it is good enough to enable the essentials to be understood (and often more).

My initial perception that the stakes were secured to a wooden beam (based on my interpretation of the photograph) is incorrect. The sharpened oak stakes, about 65cm long on average, were driven directly into the very hard clay at the bottom of the ditch. The stakes are arranged in a single row in threes - one at 60 degrees towards the enemy, one at 60 degrees towards the fort, and a third placed vertically between the other two.

The fort dates to the Claudio-Neronian period (c.40-70 AD) and a coin of Nero minted 69 AD was found. C14 samples have yet to confirm a date. The fort appears to have been deliberately abandoned and demolished. No evidence of fighting was observed. A fort of this date is apparently highly unusual in the area of the river Lahn.

Google's translation seems a little uncertain on this point but apparently small twigs, translated as 'facine works', may have topped the rampart banks (some sort of light fence obstacle perhaps). This and other destruction material such as large quantities of burnt clay is interpreted as being deliberately pulled down into the ditch over the stakes at the time of abandonment.

[Erpingham]

So, the outpost tower reconstruction is meant to illustrate the idea of the brushwood on the banks above the ditches?

It is interesting how this defence system is meant to work.  The emphasis seems to be on forcing a cautious approach by the attacker, rather than a mad rush,  and perhaps to break up a co-ordinated assault.  A small band, split into individuals, might be picked off as they closed even by a small garrison in the tower, who might in the meantime fire a beacon to summon help.  The brush on the bank tops would provide hinderance but not cover for the attacker.

[Imperial Dave]

down the ditches into spikes, up onto the ramparts to be thwarted by obstacles. An ancient version of APMs and barbed wire

[Cantabrigian]

The outpost tower reconstruction raises various questions:

Why were the banks constructed as a sort of spiral, rather than concentric rings when it seems unlikely that any attacker would ever follow the spiral as it was full of ditch?

Why are the gaps in the outer rings wider than the inner ones?

Wouldn't the gaps have been filled with something less easily removed?

[Nick Harbud]

Spiral ditches are not that uncommon.  Many of the iron age hillforts in Britain exhibit them.  One hypothesis for such construction is that it allows for incremental addition to the fortifications over several years.

[Ian61]

Spiral ditches are not that uncommon.  Many of the iron age hillforts in Britain exhibit them.  One hypothesis for such construction is that it allows for incremental addition to the fortifications over several years.

What clever idea, that makes good sense even if it is not the actual answer in all cases.