Italy
In Italy, the blackmarket football merchandise is the more frequently available - even outside stadiums! The handiest store is at Piazza Colonna on the left as you walk north on Via del Corso. It is also a ticket office for games in the Stadio Olimpico but make sure to bring your passport for ID.
Google Map: tinyurl.com/5dvzf8
The ticket is combined with entry for the Palatine, so buy the ticket from the Palatine ticket offices.
Good news! The eccentric Roman validity system for the 1 euro tickets means that they are valid for all trips starting within 75 minutes. If the machine accepts your ticket only 1 minute before expiry, the ticket is confirmed valid on that vehicle or service even if your next leg goes well over the 75 mins. And if you think you are just over the limit, try anyway - many machines run slow.
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