passage of his
troops.[84] With this object he is said to have reconnoitred in 98 and
99, and the road probably attained completion as far as the bank
opposite Orsova, about A.D. 100, as the tablet at Gradina, to
which reference has already been made, indicates. It is impossible for
us to estimate the difficulties which must have attended this
undertaking. Possessing as we do explosives and rock-borers with which
to break a passage through mountains and to blast rocky embankments, we
can hardly understand how a people, with such limited mechanical
appliances as then existed, can have surmounted the obstacles that
presented themselves to their progress. In one place the way was a plank
road resting on beams, which were driven into the perpendicular face of
the solid rock a few feet above the water's edge, whilst a little
further on it is seen to wind along terraces cut artificially, high up
on the hillsides. Hundreds if not thousands of lives must have been
sacrificed in the work, for it must be remembered that the Roman
generals and artificers had not only to combat natural difficulties, and
to overcome the same obstacles as those which our modern engineers have
to face, but that they were harassed by the savage but skilled enemy
from the heights above, or from the opposite bank of the river, which
here and there narrows itself into defiles 150 or 200 yards wide.

As soon as the road was sufficiently advanced for the passage of his
army, A.D. 101, Trajan commenced his first expedition into
Dacia. The constitution and number of his forces are not accurately
known.[85] They varied, according to different accounts, from 60,000 to
80,000 Romans, with a considerable number of allies, Germans,
Sarmatians, Mauritanian cavalry, &c., the last-named under Lucius
Quietus; and these Trajan is said to have assembled at a place somewhere
south of Viminacium, which subsequently served as the base of his
operations.[86]

Pages upon pages have been devoted by ancient and modern historians to
surmises concerning the routes taken by Trajan in his expedition and the
localities where his encounters with the Dacians took place, but in
every case the ascertained facts have been few in number. The best
history of the campaigns is delineated in the bas-reliefs on Trajan's
Column[87] at Rome, and many details have been collected from
fragmentary writings of Dion Cassius and other old historians.

For the convenience of crossing the Danube the