As early as weather permitted, late in the spring of 312, Constantine crossed the Alps with a quarter of his total army, a force equivalent to something less than forty thousand men. Having crossed the Cottian Alps at the Mont Cenis pass, he first came to Segusium (Susa, Italy), a heavily fortified town containing a military garrison, which shut its gates to him. Constantine ordered his forces to set its gates on fire and scale its walls, and took the town quickly. Constantine forbade the plunder of the town, and advanced into northern Italy. At the approach to the west of the important city of Augusta Taurinorum (Turin, Italy), Constantine encountered a large force of heavily armed Maxentian cavalry, labeled "clibanarii" or "cataphracti" in the ancient sources. In the ensuing battle Constantine spread his forces into a line, allowing Maxentius' cavalry to ride into the middle of his forces. As his forces broadly encircled the enemy cavalry, Constantine's own cavalry charged at the sides of the Maxentian cataphracts, beating them with iron-tipped clubs. Many Maxentian cavalrymen were dismounted, while most others were variously incapacitated by the blows. Constantine then commanded his foot soldiers to advance against the surviving Maxentian infantry, cutting them down as they fled. Victory, the panegyrist who speaks of the events declares, came easily. Turin refused to give refuge to the retreating forces of Maxentius. It opened its gates to Constantine instead. Other cities of the north Italian plain, recognizing Constantine's quick and clement victories, sent him embassies of congratulation for his victory. He moved on to Milan, where he was met with open gates and jubilant rejoicing. He resided there until the middle of the summer of 312 before moving on.