Few graffiti artists expect their work to last more than a few days before it is removed.
But one piece found in a Dundee University building has lasted for nearly 200 years.
The graffiti was uncovered during renovation work on Hawkshill House in the 1990s and shows support for Caroline of Brunswick, who was the wife of George IV and queen from January 1820 until her death the following year.
She and George had married in 1804 but separated a year later. When George was crowned king in 1920 he swore she would never become queen and attempted to divorce her.
However, Caroline, who was popular with the public, successfully fought a legal battle to retain her royal status, as the graffiti celebrates.
It states “Long live Queen Caroline for she has triumphed victoriously” and is dated January 12, 1821.
A picture of the historic graffiti was posted this week by Dundee University Museum as part of Museum Week 2015.
Some graffiti found on our office building! Not the "I woz 'ere" we're used to seeing! #architectureMW #MuseumWeek pic.twitter.com/7Gg7lAh84C
— Dundee Uni Museums (@UoD_Museums) March 25, 2015
George IV banned Caroline from attending his coronation and turned her away from the doors of Westminster Abbey when she did turn up.
Dundee University musuem curator Matthew Jarron said: “We know the house was built in the 18th century and refurbished in the 19th century, which is when the graffiti dates from.
“We discovered it when the building was remodelled in the late 1990s.”