What Mountain range that protected Rome from harsh weather and easy foreign invasion?

The Apennine Mountains served as a natural barrier that protected Rome from harsh weather and invasions. This mountain range runs down the length of Italy, providing a shield against cold northern winds and facilitating a more temperate climate in the region. Additionally, the rugged terrain made it difficult for invading armies to penetrate deep into the Italian peninsula, contributing to Rome's security and stability during its early expansion.