At your first port of entry you will be issued a Transit Log. This costs about €30 for non-EU vessels. EU vessels get something similar but it is called something different.
You are only required to present the transit log when in port, or when requested by authorities. Some cruisers only submit the transit log when requested and this may save on dockage fees and aggravation.
Being super cautious, with a preprogrammed fear of authorities, I dutifully submitted my transit log in almost each port that we visited where we tied to the dock. Sometimes they were surprised to see me and were not sure what to do with it.
In almost all cases I was charged a small fee (about € 4/day) for dockage and they stamped my log in and out.
We got our transit log in Zakinthos. A self appointed dock agent took our passports and ships papers and returned the next day with our new transit log (30 Euros) and his bill for €20. We later learned that we could have got our own transit log and avoided his fee, but I do not regret making use of his service and would probably do the same again next time.
At the end of my stay in Greece I turned in my transit log without any problems in Simi. I had actually anchored in the adjacent bay, Pedi, and caught the bus over the hill to Simi town.
I had to see the port police on the far side of the port and then the coast guard that kept the transit log.
Howard and Jayne [ Just Imagine ] 23-Feb-2007