THE MORAVA-YARDAR TRENCH

The Maritza takes a direct course toward Constantinople for more than one hundred and fifty miles, then turns abruptly southward to the Mediterranean Sea. At this sudden bend in the river stands the fortified city of Adrianople. Except for a short distance below the city, the Maritza no longer serves as part of the great pathway to Constantinople, but becomes a segment in the natural moat, consisting of the Tundja and lower Maritza valleys, which in the past has repeatedly provided Constantinople with an admirable first line of defense against aggression from the west. Above Adrianople the river is too frequently obstructed with sandbars to be of much use for navigation, but its broad basin carries the road and railway which follow the southern bank of the stream. South of Adrianople the small Ergene River flows to the Maritza from the east, and its valley offers a very gentle grade which the railway ascends till within a few miles of Constantinople.

THE MORAVA-YARDAR TRENCH

Second in importance to the Morava-Maritza corridor is the deep trench which cuts through the Balkans from north to south, connecting Belgrade with Saloniki. The Morava-Yardar depression does not lead to the land bridge uniting Europe with Asia Minor, but it does serve as a most important outlet channel from the plains of Hungary to the Mediterranean Sea, and is one of the shortest routes from Central Europe to the Suez Canal. From southern Germany and the eastern Alps, the foothills of the Carpathians and the Alps of Transylvania, and from all of the great Hungarian basin, the valley routes lead straight to Belgrade, whence the Morava-Yardar valley cleaves a way through the mountains to the open waters beyond.

Ostrogoths entered northern Greece

It is not without reason that the Morava-Vardar trench has been called the key to the history of the Balkan Peninsula. Through it ebbed and flowed the tides of repeated invasions from the dawn of history. Under Roman dominion most of it was occupied by an important military road. Through it the Ostrogoths entered northern Greece in the fifth century, A. D., while names still found on the map of Greece bear witness to the great Slav flood which, two centuries later, flowed through the trench and overwhelmed the Greek peninsula. The story of the Serb race is largely the story of a struggle for control of this vital artery of communication.