The article deals with development of mail delivery through Upper Carniola to Carinthia up to the beginning of 19th century. As well kept roads were of major importance for the progress of mail delivery the author pays suitable attrention to the roads over the Ljubelj and Korensko sedlo mountain passes. The major stress in the article is on establishing mail-connections over the Karavanke mountain-passes, transition to vehicle mail delivery, establishing mail-stations and on functioning of post.