The Inca army was the most powerful in the area at that time, because they could turn an ordinary villager or farmer into a soldier, ready for battle. This is because every male Inca had to take part in war at least once so as to be prepared for warfare again when needed. By the time the empire had reached its large size, every section of the empire contributed in setting up an army for war.
The Incas had no iron or steel, and their weapons were no better than those of their enemies. They went into battle with the beating of drums and the blowing of trumpets. The armor used by the Incas included:
Helmets made of wood, copper, bronze, cane, or animal skin; some were adorned with feathers
Round or square shields made from wood or hide
Cloth tunics padded with cotton and small wooden planks to protect the spine
The Inca weaponry included:
Bronze or bone-tipped spears
Two-handed wooden swords with serrated edges
Clubs with stone and spiked metal heads
Woolen slings and stones
Stone or copper headed battle-axes
Bolas (stones fastened to lengths of cord)
Roads allowed very quick movement for the Inca army, and shelters called tambo were built one day's distance in travelling from each other, so that an army on campaign could always be fed and rested. This can be seen in names of ruins such as Ollantay Tambo, or My Lord's Storehouse. These were set up so the Inca and his entourage would always have supplies (and possibly shelter) ready as he traveled.