One of the earliest erotic graffiti consisting of large phalluses and revealing sexual desire shared between two men is found in Aegean Island in Greece.

The graffiti of large phalluses carved into Astypalaia's rocky peninsula at Vathy, dated fifth and sixth centuries BC, were discovered by Dr Andreas Vlachopoulos, a specialist in prehistoric archaeology.

"So monumental in scale, they were what I would call triumphant inscriptions," Vlachopoulos told The Guradian.

Vlachopoulos said that the graffiti were exceptional as the inscriptions revealed that whoever wrote them knew how to claim "their own space in large letters that not only expressed sexual desire but talked about the act of sex itself."

The rock carvings went as explicit as one proclaiming that "Nikasitimos was here mounting Timiona (Νικασίτιμος οἶφε Τιμίονα)."

"We know that in ancient Greece sexual desire between men was not a taboo. But this graffiti ... is not just among the earliest ever discovered. By using the verb in the past continuous [tense], it clearly says that these two men were making love over a long period of time, emphasising the sexual act in a way that is highly unusual in erotic artwork," Dr Vlachopoulos explained.

There were also graffiti of two large penises carved into limestone under the name of Dion that dates back to the fifth century BC.

"They would seem to allude to similar behaviour on the part of Dion," Vlachopoulos said.

Angelos Matthaiou, the epigrapher, said that aside from becoming one of the world's erotic graffiti, the inscriptions found also revealed that the ancient humans were literate in a very impressive level.

"Whoever wrote the erotic inscription referring to Timiona was very well trained in writing. The letters have been very skillfully inscribed on the face of the rock, evidence that it was not just philosophers, scholars and historians who were trained in the art of writing but ordinary people living on islands too," Matthaiou said.

The latest gay graffiti joins the numerous contributions of the Ancient Greeks to modern culture.

It was also the Greeks who bring the modern world the practice of waxing, salons and tanning booths, according to Dr Alastair Blanshard speech titled Beauty and The Greek delivered in the University of Sydney in August 2013.

"Certainly things like hair removal and the idea of the hairless body absolutely stems from Greece," Blanshard said.

He said that ancient Greeks were discreetly vain.

"Every parent wanted to have an attractive child but they didn't want to have a child that is so attractive that the gods notice it. If you're too beautiful the gods notice you and disaster happens."