The ferry from Milos to Piraeus Port in Athens will take roughly 3 hours and 20 minutes with stops to Sifnos and Serifos if you’re taking the SeaJets Naxos Jet like we did.
Of course, you could totally start your Greece itinerary with Athens and from there start island hopping with ferries afterwards.
Take the subway from Piraeus to your accommodations in Athens. If I were you, I’d try to pick something within walking distance to Acropolis and the historic core of the city.
The focus is of course on the archeological wonders that centre around the Acropolis. There is much to discover so there’s no time to waste!
Grab something quick to go at one of the spots you pass by along the way and make your way on foot to Hadrian’s Gate.