FR 6301 then KU 1 at Barcelona
Sofia → Barcelona → Belgrade
Timetable, Barcelona time
23:15FR 6301 from Sofia at the gate
13:30KU 1 to Belgrade leaves the gate
14 h 15 apart on the timetable, overnight
KU 1 leaves 14 h 15 after FR 6301 arrives on the timetable: more than half a day, so not a connection we count.