Castelletto is a large and diverse MGA located in the eastern part of Monforte d’Alba, stretching across a range of elevations and exposures on steep, well-drained slopes. The soils are predominantly compact clay and limestone, yielding firmly structured wines with dark fruit, deep tannins, and pronounced mineral tension. Castelletto is known for producing powerful, ageworthy Barolo with a cooler, more austere profile than the warmer western slopes of the commune, often requiring time to reveal its full complexity.