The south-eastern side of the Acropolis is taken up by the Museio Hill, commonly known as Philopappos Hill. Its ancient name makes it fairly obvious that there must have been some sort of shrine dedicated to the Muses there, even though Pausanias assures us that it was really a monument in the memory of the musician Musaios. The hilltop was surrounded by fortification walls erected by Demetrius the Besieger, pretender to the Greek throne, in 294 B.C. Today the most important temple crowning the hill is the funerary monument of Philopappos that contains his burial chamber, visible from all the surrounding areas and a familiar feature of the urban landscape. This monument was built around 115 B.C. in honour of Julius Antiochus Philopappos, the grandson of the last king of Commagene, a Syrian kingdom that was abolished by the emperor Vespacianus in 72 A.D. Philopappos was probably expatriated and sent off to Athens in a more refined form of exile, where he settled down and was granted full citizenship.
    Being the wealthy offspring of a royal family, he became a great benefactor of the city and in return the Athenians allowed him to build his funerary monument on top of the Mouseio Hill, right across the Acropolis - a very honorary spot.  
     The monument is made of white Pentelic marble and faces the Sacred Rock of the Acropolis. The frieze bears a relief representation of Philopappos on a chariot while on a second level, right above the chariot, there are two niches with the seated statues of Philopappos and his grandfather, king Antiochus, that still remain in good condition. The two figures are surrounded by inscriptions in Latin and Greek recording the names and the titles of the persons represented. The grave of Philopappos itself was in a sarcophagus behind the façade with the niches, on the same level with the monument’s podium. The whole construction is more than 12 meters high.