You still have to bridge the gap-buy bus or other means from last stop in GR till border point/KUlata, just in Bulgaria. Do not be surprised if that bus goes on to Sofia and will get there much quicker as the cumbersome change. The overnite train Sof-Ist has got back in service, as seat61 very well knows, since this summer and as for now runs on-unknown for how long and if here will be a winter break. Sof Counter/INtern. has been reported closed on SUNs lately. Buy the RES-for seat or couchette, at SOF-or if closed, by conductor. You also need to RES the trainride in GR by Hellenic train.(recently renamed from TrainOSE)

Hello! The Sofia-Istanbul Express runs in both directions, every day in the evening. You can book your seat reservations at the train station in Sofia and Istanbul.