Plato mentions the Lyceum in his book Lysis, telling of Socrates walking down a road from the academy to the Lyceum to meet his friends Hippothales and Ktesippos close to the Panops springhouse. Strabo mentions the springhouse in his story and mentions that it is near the Lyceum and the Ilissus river flows from above the Agrai and the Lyceum. Lastly, Xenophon says that the Lyceum served as a meeting place for the Athenian troops when the Spartans raided the city from east of the city to their encampment at Dekelaia. Within the Lyceum were many areas serving different purposes. A few were the apodyterion, dromoi, peripatetic, palastra, and gymnasium. The apodyterion was a changing room that was either part of the gymnasium or the palmistry. The dromoi and peripatoi were roads that ran from the east to the west through the modern-day Syntagma square and Parliament building. The palaistra was a wrestling school that was used as the scene for Plato's Euthydemus. It served three functions: a training area, an area for cult activity, and a meeting place for philosophical discussion. The gymnasium was repaired in the 330s BC, but it is thought to have been originally built by Pericles in the fifth century or Pisistratus in the sixth century. The Lyceum was used at a location for philosophical discussion before Aristotle's school was founded there. Socrates, Protagoras, and Prodicus of Chios travelled to the Lyceum during fifth century BC to teach, debate, and discuss their findings. Isocrates also taught rhetoric at the Lyceum during the fourth century BC. Aristotle returned to Athens in 335 BC and established a school in one of the buildings of the Lyceum, lecturing there as well as writing most of his books and collecting books for the first European library in history. Aristotle had always been a book collector and the library grew with the books Alexander sent him, he also sent plant and animal species that allows for Aristotle to open a museum. The library attracted many scholars to his school, and they become teachers and conducted research. Students were able to study any subject available at the time. His school was compared to a factory that made professionals of any kind. In 335 BCE, Athens fell under Macedonian rule and Aristotle, aged 50, returned from Asia.