People are only just realising why UK streets have random pipes sticking out the ground

A relatively rare sight nowadays, decades ago these random pipes sticking out of the ground were crucial in stopping the stench of raw sewage getting up people's noses. Now it seems some people are only just realising these soaring structures at the side of roads are in fact stink pipes.

Usually found above sewers, stink pipes, also known as stench pipes, are reminders of the Victorian era, when cities such as London suffered from the smell of untreated waste.

The "Great Stink" during the sweltering summer of 1858 in the capital led to engineer Joseph Bazalgette putting forward proposals to channel waste through sewers, leading to pipes that would take the waste to a tidal section of the Thames where it would be swept out to sea.

Before then, most human waste was dumped in cesspits as there were relatively few flushing loos. In 1858, the stench of untreated waste spread across the city, turning up the noses of the country's MPs.

Made of cast iron, often mounted on decorative bases and situated along main sewer routes, stink pipes formed part of the Victorians' new sewer system, providing spaces to ventilate networks.

Typically green or grey in colour, hundreds of stink pipes can still be seen in towns and cities in the UK, modelled after those installed in response to the "Great Stink".

They often now appear cut in half and are obsolete because of advances in sewage processing since the 19th century.

The website, Londonist, has said there are a few tell-tale signs which set stink pipes apart from street lights, with the former being taller at six to eight metres and wider (15cm) than most poles found on Britain's streets.

According to the same publication, stink pipes ventilate a cocktail of methane, hydrogen sulphide and ammonia, all of which are flammable and stink.

A stink pipe in Shifnal, Shropshire, was listed Grade II by Historic England in April last year, in a bid to protect and recognise its rarity.

Found behind the Jaspers Arms pub, that pipe is still its full height and according to Historic England "displays a degree of artistic interest" which shows it was designed for "public pride" and more than a "purely functional structure".

A recent Reddit post prompted an array of responses when a user shared a picture of a stink pipe and asked what it was.

One Reddit user suggested it was an old street lamp while another said they had always assumed the pipes were a remnant of when gas was used to light the streets.

Others knew exactly what the pipe was used for, including one person who called it a "fart funnel" and another who dubbed it a "pong pipe".