From Bari to Brindisi there are plenty of regional trains that require no reservation, and some intercity and frecciarossa trains that do (but better avoid those for this relatively short journey). If you want to travel on one of the regional trains, simply activate your pass and add that trip to your pass shortly before taking the train and you’re ready to go.

If you're looking to travel far in the future, timetables might not yet be complete. Look for a dater closer ahead to get an idea.

If Bari-Brindisi is the only journey you’re making that day, it might not be worth it to use a travel day. A regional ticket costs €10,30 for that trip.

Bari to Brindisi has regular trains, at least one an hour.

If you are not seeing any then either you are looking too far in advance (after mid June) and the timetables have not been released yet or you are looking in the wrong place.

Search for a closer date and you can see the general times, they generally do not change much.

There are a mix of unreservable regional (RV) trains and compulsory reservation Intercity or Frecciarossa trains (IC, FR)

For the regional trains then you just add a train to your pass and travel, for the others then look at this link for making reservations. https://www.seat61.com/interrail-and-eurail-reservations.htm

I’d go for the regional trains on this route, there isn’t a big time difference and you avoid the need to pay extra.

Hello,

For figuring out which trains run on what lines don’t use the railplanner app. Use www.bahn.de/en which features almost all train schedules across Europe. Or use the operator’s site if you know which operator it is.

On Bari-Brindisi there are certainly trains (fast ones take about one hour).

When you figured out which trains you want to use, look up if you need any seat reservation for those and book them (it’s often wise to book them as soon as you decide to commit to a certain train, especially in France or on Eurostar). Here’s a handy guide for reservations: https://www.seat61.com/interrail-and-eurail-reservations.htm

Only then you enter ALL the trains (with and without reservation) into “my trip” in the railplanner. Wait to activate your pass till a few days before your trip starts. It’s kind of hard to deactivate a pass once it’s activated. If a train is not in the app, add it manually (scroll down till you see “add manually”.

See instructions about the mobile pass here: 

Hope this helps. Enjoy your trip.

Thank you all for your answers ! It makes much more sense now, and I’ve managed to find train looking at closer dates. 

However, it seems that I have to book the ferries in another web site. Could you help me with that ? 

Thanks 

The booking process depends on the ferry company. The individual pages of the Benefits portal explain how to book and how to apply the pass discount (no travel day needed):

https://benefitsportal.eurail.com/?categories=1be1ba1c-80f5-4286-b255-3092f0d486cd

If that doesn't work for you, then please mention route, date and departure time, so people can have a look.