I was told that these squares were 600 miles across (give or take).
Its a little hard to get my head around that much land.
Washington DC to New York city is, according to google, 229 miles by highway. As the crow flies it might be roughly 200 miles.
- So these squares are 3 times the distance from New York City to Washington.
Washington to Quebec City is likely about 600 miles as the crow flies.
London England to Berlin Germany is 684 miles by highway - 583 miles as the crow flies.
The isle of Britain is less than 600 miles nth-sth (548 by my inaccurate google earthing.)
I'm going to have to give the scale a rethink.
600x600 miles is 360,000 miles square.
The land area of Germany is only 216,998 miles.
The land area of Britain (Scotland, England, Nth Ireland) is 152,112 miles
So each of these squares is over twice the area of Britain and more than half again the area of Germany.