Final answer:
Hannibal crossed the Alps with an army comprising about 60,000 men and several war elephants to invade Italy. Despite winning several battles against Rome using clever tactics, he could not capture the city due to the lack of siege equipment and limited local support. Eventually, Hannibal was forced to return to defend Carthage, leading to his defeat at the Battle of Zama.
Step-by-step explanation:
Hannibal crossed several geographic obstacles to reach Rome during the Second Punic War. His journey, starting from Hispania (present-day Portugal and Spain), included traversing the formidable Alps mountains. This treacherous trek led Hannibal and his army into Italy, where he aimed to weaken Rome's alliances and take the city.
His army primarily consisted of around 60,000 men and several war elephants. Although the harsh conditions of the Alps killed most of the elephants, the survivors made a significant psychological impact on the Roman forces. Throughout his campaign in Italy, Hannibal deployed ingenious tactical maneuvers to defeat the Romans in battles such as Trebia, Lake Trasimene, and Cannae. Despite these victories, Hannibal lacked a siege train for attacking heavily fortified Rome and struggled to gain support from the Italian peoples previously subjugated by the Romans.
Eventually, his army's strength dwindled due to Rome's successful efforts at preventing reinforcements from reaching him from Spain and Africa. The war shifted when a Roman force led by Publius Cornelius Scipio invaded North Africa, forcing Hannibal to return and defend Carthage. The conflict concluded with the Battle of Zama in 202 BCE, where Scipio's troops defeated Hannibal, ending Carthage's ambitions and extending Rome's dominion.