They vary somewhat in size.

The larger 'insulae', which lie west of the main north and south street, are oblong and measure about 150 x 100 yds.

(say, 3 acres); many smaller ones are more nearly square (98 x 98 or 109 yds., about 2 acres).
But the regularity of the plan is plainly the work of civilized man.
When the Celts were brought to live in a Roman city, care was taken that it should be really Roman.[104] Only we may perhaps wonder whether the plan may not have been drawn by Augustus with an eye more to the future than to the present and may have included more 'insulae' than there were actually inhabitants to occupy at once.

That was the case certainly in the mediaeval English town of Winchelsea, where the rectangular building-plots laid out by Edward I have in great measure lain empty and untenanted to the present day.
[104] H.de Fontenay, _Autun et ses monuments_ (Autun, 1889), pp.
49 foll.

and map (1:6,250).