Approaching Mount Somma from the east, four ridges are encountered: The highest point of Mount Somma, at 1,132 metres (3,714 ft), is called "Punta del Nasone" (literally "tip of the big nose") because of its similarity with a nose covered in the profile of a face lying along the top of the mountain and probably also referring to King Ferdinand I of the Two Sicilies, popularly known as "Re Nasone" ("Big Nose King").

This similarity can be seen by looking at Mount Somma from Vesuvius's peak while Ferdinand I is well known himself for the advanced approach he had to Somma-Vesuvius volcanic complex, giving support to geological research and improvement of the area.

In March 1944, a spectacular lava flow interrupted the north outline of the mountain down to the towns of San Sebastiano al Vesuvio and Massa di Somma.

9 in the numbering of the Vesuvius National Park) allows visitors to cross the entire flow at a width of almost 200 metres (660 ft).

It looks like a natural amphitheatre on top of which is located the Olivella spring; a short distance from the outlet is a stone arch that was part of an aqueduct, built in the time of King Ferdinand I to convey water to Naples.