When approaching from Castelnuovo Berardenga the hamlet is reached through the Siena Gate. The immediate impression of a old fortified medieval hamlet is strengthened by the miniature-like streets and the piazza which provides housing for only a dozen or so inhabitants.The 'Lodo di Poggibonsi' confirmed S.Gusmè to be in the territory of Siena as it lies on the border of the Florence and Siena territories. It is surrounded by walls and overlooked by the Florentine castles of Brolio and Cacchiano making it a charming hamlet to visit. The name derives from Cosmo, one of the Saints to whom the local church is dedicated (the other is Damian). The church, documented from 867, was originally in Campi Castle and was rebuilt in the nineteenth century.
A few kilometers from S.Gusmè are the notable archaeological sites of Campi and Cetamura. Also near S.Gusmè is the medieval hamlet of Villa a Sesta, so far untouched by tourism.