Especially impressive is that section around Monastir, toward the frontier of Albania and away from the main line of the railroad. Here, not more than a day's walk from the city of Monastir, or Bitolia, as its Slavic inhabitants call it, is Lake Prespa, a small sheet of crystal-clear water in which are reflected the peaks and the rugged crags of the surrounding mountains. Through a subterranean passage the waters of this mountain lake pass under the range that separates it from the much larger lake, Ochrida, the source of the bloody Drina. The people of these mountains are Serbs, almost to Saloniki. Uskub, whose ancient Serb name is Skoplya, was the old Serb capital, and there the Serb ruler Doushan was crowned emperor in 1346. For the past five hundred years these Macedonians have been used to all the ways of guerrilla fighting. Roaming through their mountains in small bands they have harassed the Turkish soldiers continuously. The Bulgarian ruler Ferdinand had through many years by means of committees and church jugglery striven to Bulgarize this population, preparatory to the contemplated seizure of the territory which he has now been able with the help of the Germanic powers to accomplish. But in reality the Bulgar population in what was European Turkey was found only eastward of the Struma in Thracia including Adrianople. Those regions formed the ample and legitimate field of ambition for the unification of the Bulgars. When hostilities broke out in 1914, when Serbia was defending herself against the Austrians, King Ferdinand of Bulgaria, the secret ally by treaty of Austria, did everything possible to forward his designs against the Serbs and sent armed Bulgar bands into Serb Macedonia. Shortly below the city of Monastir in the west begins the Greek frontier, running over eastward to Doiran, where it touches the Bulgarian frontier. Here the railroad, coming down along the Vardar River, emerges into the swamp lands and over them passes into the city of Saloniki. Here is the old territory of Philip of Macedon, the father of the conqueror. For some forty or fifty miles these swamps stretch out from Saloniki, overshadowed by Mt. Olympus on their southern edge. While not quite so extensive as the Pinsk Swamps, they are quite as impassable, from a military point of view. In the center of this region of bulrushes and stunted forests is an open sheet of shallow water, Lake Enedjee. Nearly all this swamp land is submerged, but here and there are small islands. For some years the Turkish soldiers garrisoned these islands during the mild winter months, living on them in rush huts. In the summer they would withdraw into the near-by foothills. But one summer several hundred Comitajis descended into the swamps and took possession.