Civilian populations on the side of the Allies felt the direct hardship of enemy occupation. The vast majority of Belgians and many of the residents of northeastern France spent the war under German military administration. In Poland, western Russia, and the Balkans as well, the violence of the war pushed a multitude of European civilians from their homes. Fleeing battered cities and hostile armies, entire families took to the roads to find shelter elsewhere. Out of Belgium's population of 7.6 million, 1 million fled their country, taking refuge in the Netherlands, France, and Britain. In the fall of 1915, the full force of the war struck the population of Serbia, as the country was flooded with Austrian, German, and Bulgarian troops. Large numbers of civilians accompanied the remnants of the Serbian army, escaping from their beleaguered country westward over the mountains of Montenegro and neutral Albania to the Adriatic Sea. Out of a force of 170,000 soldiers, 30,000 did not live to reach the ports of Valona and Durrazo for evacuation. An equal number of civilian refugees died in the harsh journey through the mountains. Sometimes occupation brought massacres. As German forces pushed through Belgium in August 1914, they often responded in a brutal and massive way to suspected civilian snipers. In the province of Brabant alone, for example, 839 Belgians were executed and the center of the historic city of Louvain was burned. Even as the enemy pulled out, the cost to civilians was high. The German army's strategic retreat on the western front in spring 1917 was accompanied by a wave of destruction of French territory; wells, orchards, mines, and houses were systematically wrecked.