Rome grew from a small village 509bce to the ruler of most of the Italian peninsula 244 years later. Rome would later develop into the greatest western empire of the ancient world. The city was protected from enemy invasion by seven hills and a shallow river. From the hills the Romans could see enemies approach. Experienced Roman sailors with small ships were able to navigate the Tiber River, but the river could not accommodate large s__a__o__ng vessels necessary to attack the city.