Short answers, pulled from the story.
The Italian Peninsula stretches into the central Mediterranean Sea from the southern Alps to the sea's edge. Locals call it lo Stivale, which means the Boot, because its shape resembles a high-heeled boot.
Touring Club Italiano published details about these physical features in 1957. The Apennine Mountains run through the center of the region like a spine and separate the eastern coast from the western coast along most of the length.
Mount Vesuvius stands as the only active volcano on continental Europe within this specific area near the city of Naples on the western side of the boot. No other active volcanoes exist on the mainland portion of the continent here.
Three political entities occupy the strict sense of the peninsular area: Italy contains virtually the entire peninsula with 26,140,000 people, San Marino exists as a central-eastern enclave covering 31 square kilometers, and Vatican City is an enclave inside Rome spanning just 829 square meters.
A line drawn from the Magra River to the Rubicon River marks the minimum extent of the territory. This boundary excludes the Po Valley and the southern slopes of the Alps.