Not much can be found online regarding the real need of having this document while sailing in Italian waters or the details on how to get it and the places it needs to be stamped.
Most information available is the result of other sailors experiences and even then there’s a lot of confusion with people saying they sailed for years, months in Italy and never been issued or requested for one...
The simple part:
All the Non-EU flagged pleasure vessels sailing in Italy are required to obtain a "Costituto" (transit log) in the first Italian port of call, and they are obliged to return it at the last port of call before exiting Italian waters.
The document contains the information regarding the vessel, ownership, crew and passengers.
The not so clear part:
Depending on the harbourmaster official (from Guardia Costeria - Capitanerie) or office this document needs to be stamped in each port/capitanerie or just on a few listed locations (listed in fine print at the bottom of the page reserved for the stamps).
Our strategy was to try and stamp it in the majority of ports.
Because it wasn’t always easy to find the relevant Guardia Costeria - Capitanerie office we took note of the offices' locations for our future reference if needed or just to help anyone that also needs to find them.
Sardinia - Alghero
Elba - Porto Azzuro