@hazardwarning just to make life interesting, there were parts of the same area code in THE US that were technically considered "out of area" calls. Large parts of the 408 area code were also in different LATAs [en.m.wikipedia.org] which meant you needed a PhD to figure out whether or not the 7 digit "local" number you were about to dial was going to require a small bank loan to pay the resulting phone bill.
/@matigo