Tourism seasonality index across ~7,900 comuni, from ISTAT. Pan and zoom the map, or search a place to see its figure and open its full profile.
How it’s built. 1 minus the ratio of the quietest month's tourist-accommodation nights spent (presenze) to the busiest month's, from ISTAT's comune-level monthly occupancy survey, 2024 (the newest year not flagged provisional in the source — 2025's own rows are 100% flagged '(f)'). 0 means visitor nights are spread evenly across the year; a value approaching 1 means almost all of the year's overnight tourist stays happen in a single month. A raw peak/trough ratio was deliberately not used: it is undefined whenever any month records zero presenze, a real and unremarkable outcome for a small seasonal town's quietest month.