Ἰταλία

Acts 18:2 Ἰταλίας, Italy,

There he found a Jew named Aquila, a native of Pontus, who had recently come from Italy with his wife Priscilla because Claudius had ordered all the Jews to leave Rome. Paul went to visit them,

Here: Italy, the Roman heartland. The rest of the verse makes clear that Rome itself was the city they left.

Acts 27:1 Ἰταλίαν, Italy,

When it was decided that we would sail for Italy, Paul and some other prisoners were handed over to a centurion named Julius, who belonged to the Imperial Regiment.

Here: The Italian peninsula, meaning Rome, where Caesar's court would hear Paul's appeal (25:11–12; 23:11).

Acts 27:6 Ἰταλίαν Italy

There the centurion found an Alexandrian ship sailing for Italy and put us on board.

Here: The Italian peninsula. The ship's actual destination was probably Puteoli (or perhaps Ostia), the main harbours for Egyptian grain. Paul was being sent to Rome to have his appeal to Caesar heard (25:11–12; 27:1).

Hebrews 13:24 Ἰταλίας. Italy.

Greet all your leaders and all the saints. Those from Italy send you greetings.

Here: The Italian peninsula, whose centre was Rome. Elsewhere in the NT only in Acts 18:2 (Aquila 'recently come from Italy'), Acts 27:1, 6 (Paul's voyage).