Calling all armchair generals! Boudica's Last Stand.

[Nathan Ross]

I make the distance from the Menai Strait to London as being c. 270 miles which, at 20 miles per day, works out at 13.5 days. 

I was just comparing John's estimate of the Anglesey to London distance, by what I would take to be the quickest route. Now I come to measure it accurately, I make it a little over 235 miles using the Google Maps measuring tool, following the route of Watling Street and what seems to be the Roman road along the north Wales coast. That would be about 13 days at 18 miles per day, or 11-12 at 20 miles a day. There would probably have been pauses en route, even if Paulinus did not detour back to Wroxter on the way:

   

Suetonius' plan... was to take the 14th Legion, rendezvous with Cerialis and the 9th and together go to the relief of the colony... when he heard of the fall of Colchester and the defeat of Cerialis, Suetonius proceeded to Godmanchester (if he was not already there) and then down Ermine Street to London... By this route, the distance from the Menai Strait to London is c. 298 miles

I think that is absolutely right, and I've been going along with that scenario for a while now. The distance doesn't appear to be that great though - I make it 252 miles via Leicester and Godmanchester:

   

As to how long it would have taken for Suetonius to get news of the threat to Colchester, I calculate that, with sufficient remounts and relief riders, a message could have been got to him within 24 hours.

Yes, probably. And the 'threat' could have been registered some time before the actual revolt broke out - Decianus had time to send a small detachment of troops to Colchester.

But anyway, all of these estimates bring the timescale of Paulinus hearing about the revolt, or threat of it, and getting his men down to London to within a fortnight at most.