GQ 820 then FR 3181 at Fiumicino
Athens → Rome → Barcelona
Timetable, Rome time
12:00GQ 820 from Athens at the gate
11:50FR 3181 to Barcelona leaves the gate
23 h 50 apart on the timetable, overnight
FR 3181 leaves 23 h 50 after GQ 820 arrives on the timetable: more than half a day, so not a connection we count.