k that should begin from another quarter.

The Austro-Serbian frontier, almost 340 miles in extent, is formed on
the north by the Save as well as by the Danube, and on the east and
southeast by the Drina River. These two smaller streams abound in
convenient fords, especially in summer. To many of these points on the
northeastern frontier Austria had already constructed strategic
railways. Moreover, the Austrian territory throughout this section is so
mountainous and well timbered that large forces of troops could be well
screened from observation, whereas the country opposite Belgrade is flat
and bare.

It was from this direction that the Serbian General Staff expected the
first advance of the enemy. And yet there were dozens of other points
where an attack in force was possible. Each must be covered with a force
at least strong enough to hold the enemy back long enough to enable the
forces stationed at the other points to come up to support. Here was the
great advantage that the Austrians had to begin with; an advantage which
the attacking army always enjoys. The attacking general alone knows
where the first battle shall be fought.

The Serbians, therefore, could not count on meeting the Austrians in
full force before they could enter Serbian territory. They realized that
they must give way at the first contact; that the Austrians would
undoubtedly advance quite some distance within Serbian territory before
enough Serbian forces could be brought up against them to make the
opposition effective.

Realizing this, it was decided to place fairly strong advance guards at
all probable points of invasion with orders to resist as long as
possible; until, in fact, defensive tactics could be adapted to the
situation and the main Serbian army could be brought up to offer battle.

However, two points stood out as the most probable. These were the two
already mentioned; the north, along the line from Obrenovatz to Belgrade
and to Semendria; or, the front Obrenovatz-Ratza-Losnitza-Liubovia. The
first possibility had the advantage to the Austrians of offering the
shortest route to the center of the country--the Morava Valley, their
natural objective. But it also necessitated a difficult crossing of the
Danube, which would have had to be preceded by the building of pontoon
bridges. This would have given the Serbians time to move up their main
forces. The second alternative, an invasion from the east, would have
entailed a longer