I only see pigeons in highly urbanized areas.
Where did pigeons live before Man built all of his cities?
Northern Africa, on rocky ridges; from there to buildings wasn´t much of a change.
Cliffs. City pigeons (Columba livia) are more properly called rock pigeons. This is why they like buidings and window ledges.
We obliged them immensely by building large numbers of cliffs, complete with lots of ledges for nesting, that are ideal habitat for them in lots of places where there formerly was none.
OK, cliffs, not ridges; my mistake. Sorry. :o