No idea about the railway bridge bit but in December, the exact dates I’ve forgotten but it was very close to Christmas, 50-100 cameras were put on lamposts, trees, dedicated posts bolted into the tarmac and even bins. This all took place in about 24 hours, they were there for maybe 36 hours and then everything was gone.
This happened right on the edge of the County Of Cardiff and mostly in the Vale Of Glamorgan over a quite small area, maybe 9 or 10 square miles. To this day no one really knows what it was all about but they appeared to be networked. At the bare minimum ‘phoning home’ often.
I got stuck behind a van that had been stupidly parked and watched a bloke install one of the cameras, lots of wires that were seemingly electrical and what looked CAT5/6 cables which went into a box that he put, what looked to me like a Doro mobile, in.
All the numbers of cameras, time scales and so on are speculation, based on my own observations and those of people I know and trust.
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