Poros is a small Greek island in the Saronic Gulf. It’s literally only about an hour and a half by high speed ferry, but I much prefer the slow ferry – two hours but you can wander around the deck and not be strapped to your aeroplane seat. After all, the journey is what it’s all about.
I find it’s not so well known by the international tourists, who usually come to Greece and visit Santorini, Mykonos or Crete. Some venture further afield, but even then they may not consider the smaller, nearer to Athens Greek islands. You’re missing out.