I am starting a cruise in Athens. I would like to go in early to see more of the sights. The cruise includes a full day in Athens. How many extra days do I need?
It all depends on what interests you. For the major archaeological sites alone, you'll need two full days Most of them are located in the same largely pedestrianized area.
Add a day or two to see museums, many of which are also located in the same area.
If you're tired of ruins and museums and want to see the city in a different way than rushing from one site/museum to another, add another day or two.
So, to find a compromise between the time you have and enjoying Athens, let's say 3 or 4 days is a good amount.
By the way, there's no point in taking the Hop-On Off buses; you won't see anything except the busy, polluted main avenues of Athens.
The official Athens website:
I don’t have an answer to your actual question. If you are going to spend some time in Athens before the cruise, you might want to use your day of cruise excursions to see something outside of the city .