Eis a canção mais antiga que nos chegou integralmente: Seikilos Epitaph - Song of Seikilos - Σείκιλος

The Seikilos epitaph is the oldest surviving example of a complete musical composition in the world, and the oldest surviving example of Ancient Greek musical notation for that matter. 

The melody is inscribed on top of the lyrics on a tombstone stela, that was found near Aidinion, current day Turkey (in the vicinity of Ephesus), where a woman was using the block of marble as support for her pigeon water hole. It was subsequently lost for a few decades after the 1921-1922 Greek Asia Minor genocide by the Turks, and having survived that catastrophe virtually unscathed, it then resurfaced in Smurna where Turkish railway Director Edward Purser's wife had the bottom sawed off so that it would stand nicer for her garden's flowertops. This obliterated one line of text. The Dutch Consul saw it by chance and brought it via Constantinople to the Hague and then to Copenhagen for safe keeping during the war, where it has been "kept safe" ever since, like all other antiquities in museums around the world. 

It is dated 200 BC to AD 100, meaning this particular musical notation was well established since at least the 3rd century BCE, perhaps the 4th, but it is likely during the time of Homer, 8th BCE, there was another type of notation predating this one. 

Other examples of ancient Greek songs with extant musical notation include the Delphic Hymns, but these are not "complete", but fragmentary. 

The following is a transliteration of the words: 

Hoson zēis, phainou 

Mēden holōs su lupou; 

Pros oligon esti to zēn 

To telos ho chronos apaitei. 

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On the top, the epitaph reads: 

Εἰκὼν ἡ λίθος εἰμί. 

Τίθησί με Σείκιλος 

ἔνθα μνήμης ἀθανάτου 

σῆμα πολυχρόνιον. 

Which roughly translates to: 

I am this stone, an icon 

Seikilos placed inside me 

an everlasting simulacrum 

of deathless remembrance 

...and might we say, indeed he did. 

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at the bottom, there is also a brief inscription 

Σείκιλος Ευτέρπῃ 

Which roughly translates to: 

Seikilos to Euterpre 

Some scholars argue it is his wife, others his daughter or lover. The most plausible is the Muse Euterpe, given the type of votive this is, that is, music for deathless remembrance, the words of the song about pleasure and no grievances and the idea of time. 

The picture of the stela is by "Nationalmuseets fotograf" and it is in the National Museum of Denmark in Copenhagen with inventory number 14897. 

This is an attempt at Reconstructed Ancient Greek, not Erasmian pronunciation.