Explore the ruins.
Troy was destroyed and rebuilt nine times over, and each of nine different layers still has something left to this day, although amateurish archaeological excavations of late 1800s damaged some of them a lot more than others. The layer that is thought to be depicted in Homer's Iliad is likely Troy VII, a portion of the legendary walls of which is still intact.
The admission fee to the site is 15 TL pp. Make sure that you don't accept any of the 'old' Turkish money as change from the admission office. You wont be able to use it outside of Troy for some reason certain locations still accept and distribute the old 'New Turkish Lira' and you will have to change it at a bank.