It's a perennial problem when you're standing 24/7, 365 days a year outside in the elements. Pigeon droppings. Algae build-up. Grime. Even royalty is not exempt.
However, three bronze statues of celebrated 19th century Edinburgh citizens are now sitting prettier after a team of statue cleaning specialists, joined by jobseekers from the Future Jobs Fund, gave them a clean-up over the last two months.
The monuments to famous explorer and missionary David Livingstone; former Lord Provost and publisher Adam Black; and anti-reformist and author Professor John Wilson (pen name Christopher North), can all be found in East Princes Street Gardens, between the Scott Monument and the Galleries on the Mound.
Overall the statues are in good condition, but essential conservation work was required to prevent corrosion.
The first stage of the £16,550 project involved scrubbing and gently cleaning the statues to remove all the accumulated grime, particularly algae and bird droppings which are acidic.
Finally, the bronze was re-patinated to darken and stabilise its surface, before a new layer of wax was applied to protect it.
The project was funded by the City of Edinburgh Council and Edinburgh World Heritage, together with a donation from the Mount Royal Hotel on Princes Street.
Future Jobs Fund volunteers Josh Steele and Charles Slarks said they were both now considering applying for college to further improve the skills they have learned during the statue-cleaning project.
Steele, 19, said: "It's been a really good opportunity and it's made me realise I would like to do something connected to conservation work in the future."
Slarks, 24, said: "I never would have thought I would be doing anything like this, but it's been really interesting. I've always been interested in Edinburgh's history and this job has encouraged me to learn more about it, as well as giving me useful skills. Now I would like to go to college to develop my skills further."