Annaba is best reached by air. It's airport Rabah Bitat International Airport has regular services to Paris Orly, Marseille, and Lyons. However, these frequencies aren't frequent and one should check an Air Algerie timetable when planning a trip. There are four daily flights between Algiers and Annaba. Annaba also has regular service to Oran.
There is a ferry service from Marseille to Annaba operated by, Ferries Algerie.
One can also reach Annaba by road quite easily from most major Algerian cities. However, due to the lack of quality infrastructure this is the least desirable option.