Does anyone know if this is actually a town on the flank of Mt. Vesuvius? Seems extremely foolhardy. Is that marker misplaced?

Ciao

That's a database mistake.
Brusciano is about 10 kilometers north from that point: what you see is just vegetation.
But you're right saying foolhardy because the whole vesuvian area is highly populated and, in case of eruption, at least two million people would be in serious danger.

Vesuvio, located in close proximity to the city of Naples in the Campania region of southern Italy, is most famous for its explosive Plinian eruption in 79 A.D. which destroyed and buried the Roman cities of Pompeii and Herculaneum. Other catastrophic subplinian eruptions of Vesuvio occurred in 472 and 1631. Vesuvio�s last eruption occurred in 1944, taking 24 lives and causing damage from lava flows and ash fall in communities closest to the crater, but since then the volcano has experienced its longest state of quiescence in almost 400 years (Scandone, Giacomelli & Gasparini, 1993). Approximately 3 million people now live in greater Naples, Europe�s most densely populated metropolitan area. Almost 600,000 of these reside in the �Zona Rossa� or Red Zone, an area defined in the local emergency plan that is likely to experience the most devastating effects from Vesuvio, particularly pyroclastic flows and lahars, in the event of a future subplinian eruption. Other areas surrounding Vesuvio are designated as the �Zona Gialla� or Yellow Zone and �Zona Blu� or Blue Zone. Communities in the Yellow Zone are further from Vesuvio and may be exposed to fallout hazards from the eruptive column, depending upon the direction and speed of prevailing winds during the eruption. The Blue Zone is an area that is exposed to hazards from mudflows and floods resulting from syneruptive or posteruptive remobilization by heavy rainfall of loose pyroclastic material deposited by the wind-dispersed eruptive column. Source.

Additional info.

Bye
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