Scotland and the indoor toilet
By 1970, man had landed on the moon, yet one in four Scots still had to share an outdoor toilet.
Until, that is, a group of Glasgow neighbours decided enough was enough.
They launched a battle to get indoor toilets installed in their tenements - and inadvertently changed the face of Scottish housing forever.
But that's not Scotland's only connection to the history of the "cludgie".
The Ancient Greeks are among early contenders to the claim to the invention of the toilet, but others argue that the Scots beat them to it.
According to Allan Burnett, historian and author of Invented In Scotland, the Neolithic settlement of Skara Brae in Orkney in fact boasted the world's first indoor toilet.
There is evidence of stone huts equipped with drains built into the village walls, dating back to around 3,000 B.C., he says.
The sewer system was basic - waste was flushed into a drain with pots of water - but the basic principle remains to this day.
Invention of the flush
Sir John Harington, godson of Queen Elizabeth I, is usually credited with being the inventor of the first flushing water closet in 1596 - not, as is widely believed, Thomas Crapper.
The design is described in Harington's book Metamorphosis of Ajax ("ajax" being a pun on the word "jakes" which was a Tudor name for a privy).
Harington made one flushing toilet for himself and another for the Queen, which she installed at Richmond Palace.
Sadly neither survives, but there is a replica at the Gladstone Pottery Museum in Stoke-on-Trent, which has a remarkable collection of old toilets from decorative Victorian loos to 1970s avocado bathroom suites.
It wasn't until 1775, however, that the first patent was taken out for a water closet.
It came from Alexander Cummings, a watchmaker born in Edinburgh.
His design was similar to Harington's, but was notable for its "s-trap feature" which stopped odours from escaping.
He also used swirling water to clean the bowl.
The closet was enclosed inside a wooden cabinet and had an overhead cistern using gravity to aid the flow of water for the flush.
There were numerous later improvements and adaptations by other engineers before the toilet arrived at the design we know today.
Flushed with success
By the late 1800s, indoor toilets had become the norm in new middle class homes in Scotland.
And yet, in the 1970s, in Govan in the south of Glasgow and in many other parts of Scotland, families still lived in tenement houses without an internal bathroom or toilet.
Tenants in Govan decided do something about it.
Author Raymond Young has written a book, Annie's Loo, which tells the tale of their fight for indoor loos, and how it created a revolution in social housing.
"The way the authorities were trying to deal with it was by demolishing the tenements and building new houses with inside toilets," he said.
"People wanted to move to begin with, but where they were being moved to was far away from their work, far away from their friends, far away from their communities.
"They said it might be better to stay in these old tenements."
The tenants created a residents' associations to campaign for indoor toilets in their existing homes, and housing associations which could buy up the old tenements no one wanted.
The movement was significant in creating the model for the housing associations and co-operatives that manage social housing across Scotland today.
In 1972, the first indoor toilet and bathroom was installed in the Govan tenement home of Annie Gibbons.
Media and crowds gathered to see senior local councillor Pat Lally arrive in a big black car and make his way up to the third floor to officially open Annie's loo.
He ceremonially flush the toilet for the very first time. It really was a flush of success.
You might have heard the strange claim that if someone knocks on your door in Scotland and needs to use the toilet, you are bound by law to let them enter.
This was even voted the UK's "fifth most ridiculous law" in 2008, according to the Telegraph.
However, this has been debunked by the Law Commission, which says it "cannot find evidence that it was on the statute book".
The law experts say the myth may have grown around local custom and point to Scottish people's "strong sense of hospitality".