Pausanias Description of Greece 1.25.2

[2]
  By the south wall are represented the legendary war with the giants, who once dwelt about Thrace and on the isthmus of Pallene , the battle between the Athenians and the Amazons, the engagement with the Persians at Marathon and the destruction of the Gauls in Mysia . ¹ Each is about two cubits, and all were dedicated by Attalus. There stands too Olympiodorus, who won fame for the greatness of his achievements, especially in the crisis when he displayed a brave confidence among men who had met with continuous reverses, and were therefore in despair of winning a single success in the days to come.

[2] At the south wall is [represented] the war they say was fought with the giants [ gigantes], who once dwelled about Thrace and on the isthmus of Pallene, also the battle [ makhē] between the Athenians and the Amazons, also the deed [ ergon] accomplished against the Persians at Marathon, also the destruction of the Gauls [ Galatai] in Mysia. 88

Each is about two cubits, and all were dedicated [ anatithenai] by Attalos. There stands too Olympiodoros, who won fame [ doxa] for the greatness of his achievements, especially in the crisis when he displayed a brave confidence among men who had met with continuous reverses and were therefore in despair of winning a single success in the days to come.