The opening hours of the archaeological excavations of Pompeii vary depending on the season.
From 16 March to 14 October, the excavations are open daily from 9 a.m. to 7 p.m., with the last admission allowed at 5.30 p.m.
During the winter period, from 15 October to 15 March, the excavations are open daily from 9 a.m. to 5 p.m., with last admission at 3.30
p.m. It is important to note that the excavations are closed on 1 January and 25 December.
For more information, you can visit PompeiiOnline