Location of the Frigidus River

[Robert Vermaat]

The National museum of Slovenia uploaded a reconstruction of the Ad Pirum fortress

Thanks for that one. They found 3 plumbatae here, not a small number. I guess the fort saw some fighting!

[Tormenta]

I guess the fort saw some fighting!

I'll be surprised if it didn't. This was the last obstacle before entering in "Italy". You still have Castra in the valley below, but that can be bypassed(in theory).

The idea being if one section is breached the others will still hold.

Yes, that is also the formal explanation.

[Robert Vermaat]

The idea being if one section is breached the others will still hold.

Yes, that is also the formal explanation.

Perhaps the 'extra' walled areas could be used to house cattle, or perhaps civilians in case of emergency? Or perhaps a reduced defensive force? I've never seen Roman fortresses being constructed in this manner before - i.e. with inner defences like these. To me it resembled Principate forts or cities being 'reduced' by inner walls in later times.

[Tormenta]

Perhaps the 'extra' walled areas could be used to house cattle, or perhaps civilians in case of emergency? Or perhaps a reduced defensive force?

The cattle options is also a formal explanation, but is also accompanied by the possibility of being used for cases of emergencies.
For hosting the local population of course, can be a possibility and also for hosting a defensive force. This can at least stop for a few days the advance of a barbarian force or a roman one to entering into the north Italian plains.
Not much articles are available on this(as far I know), but in the last times much effort is being putted to better present and preserve the remains.

[Tormenta]

After cautiously listening at the Rat Conference I'm correcting myself.
The complete defense system was newer used for his primary function -to repel(stop) any barbarian force, but only in wars between emperors and usurpers(Theodosius tore down it).
The upper part of the Ad Pirum fortress could difficulty host a defensive force, unless for a few days, because the slopes are too steep.

[Gaius Julius Caesar]

In between the banks on either side, obviously!

[Robert Vermaat]

In between the banks on either side, obviously!

Excellent conclusion Byron, now please locate those banks on a map for us and we're all happy. :wink:

[Tormenta]

For some photos of the site check the post in rat conference 2012.
Maybe some reconstructions of the site will available in the near future.
When available I will point out the work of the voluntaries who
walk up end down the woods, hills, mountains to detect the defensive system and who even run into bears to present their work to the public....