Their service is sometimes unfairly derided as slow, inefficient and unable to compete with the latest digital technology.
But postmen have proved old-fashioned ways of sending letters can be the best – after miraculously delivering a card to its correct destination in Lowestoft with the vaguest of address details.
The sender, from Croydon, sends former work colleagues Antony and Sarah Wren a Christmas card every year.
But after the pair moved to the coastal town from Essex over a year ago to follow their dream of living by the sea, the sender lost their new address details.
Determined to still send her season's greetings, the woman didn't bother with a postcode, house number or even a town – simply writing: 'Somewhere near the sea in Suffolk.'
She added: 'Good luck postie' beneath that and popped in the mail by second-class post – never sure whether it would ever arrive.
For all anyone knew, the letter could have been intended for someone in Aldeburgh, Felixstowe, Southwold or one of the many seaside villages in between.
Yet despite having a common surname, the letter arrived at its intended destination in Blackheath Road, Kirkley four days after it was sent.
The Royal Mail said it tracked the correct address down through the in-depth local knowledge of its postmen, many of whom have delivered letters on their rounds for more than 20 years and know the town like the back of their hands.
Mr Wren, 42, said he and his wife – who work as childminders – were astounded the Christmas card even reached them.
'If they'd looked at it and thought: 'You've got to be having a laugh,' no-one would really have batted an eyelid,' he said.
'No-one would've expected it to get here. I don't know what miracles they worked – I was quite taken aback.
'Our first reaction was: 'How did this get here?''
Inside was a letter from the sender explaining that she remembered the Wrens had moved but could not find their new details.
Mr Wren added: 'The Post Office is always getting slated for not delivering mail or being slow.
'However at this time of year, they're busier than ever and are still able to do something like this, so we should give them a break.'
Mr Wren has since tweeted the Royal Mail to say thank you for pulling off an amazing feat.
A Royal Mail spokeswoman said: 'Royal Mail is pleased that we were able to deliver this card and it is testament to the dedication of our postmen and women who have excellent knowledge of the communities they serve.'
The couple who have two children – Nathan, seven, and Aidan, three – are now in the process of writing back to the sender to fill her in on the story…using the Royal Mail, of course.
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