The cheapest flight to Sofia you can get by boooking 39 days before departure.
The most popular airlines on the route Karlsruhe - Sofia: Ryanair (FR), Air Berlin (AB), Air Serbia (JU).
The cheapest flights you can book on the route Baden-Baden (FKB) - Sofia Airport (SOF).
Direct flights last about 2h 15min.
Direct flights available 2 days a week - Wednesday, Sunday.
Direct flights: Ryanair (FR).