There used to be 2 area codes for phone numbers here in the UK.
a "I'm calling location A from location B" code, and a "Location A code when calling from _anywhere_".
The first code was cheaper.
When I was 12ish, on the way home from a holiday several counties away, my lift broke down on the motorway. So I called the operator from the nearest payphone (aiming to let my parents know I'd be late. This was over 20 years ago, very few mobile phones..), asking for my parents area code, as it was the first time I'd had to ring home from a different district.
The operator refused to give me the expensive "anywhere" code, and insisted she could only give me a code if I told her where I was calling from. I remeber getting quite hysterical at the operator, explaining if I _knew_ where I was, I wouln't be worried about what time I'd be getting home.
I ended up reading every poster near the phone at the operator till she worked out where I was and gave me the relevant code.