Certaldo is a town and comune of Tuscany, Italy, in the Metropolitan City of Florence, located in the middle of Valdelsa. It is about 35 kilometre…Certaldo is a town and comune of Tuscany, Italy, in the Metropolitan City of Florence, located in the middle of Valdelsa. It is about 35 kilometres southwest of the Florence Cathedral, and 40 minutes by rail north of Siena.