Now you have visited the Acropolis, you can visit the Acropolis museum. Not only because it´s interesting, but also because it can be bloody warm in Athens haha.
I liked the fact that there are windows everywhere in the museum, so while getting more information about the history, you can always look outside and see the Pantheon.
After the museum take a walk through the Plaka. This is an neighbourhood where you can buy mostly touristic stuff and are lots of restaurants. Maybe a little overpriced and touristy, but it is a nice place. I loved to take pictures here, it´s very picturesque. The arch of Hadrian is here as well, which is surprisingly Roman. It´s a monumental gateway that resembles a Roman triumphal arch.
Are you a European student? For the Acropolis museum you get a free admission as well! So make use of it 🙂