There is evidence that the walnut has been present in Campania since at least the first century AD. In Herculaneum, the charred remains of very similar shaped nuts to those of today have been found in the Casa D'Argo, while at Pompeii, paintings portraying walnuts have come to light in the Misteri Villa. The soil and climate in Campania are particularly favourable to the cultivation of this crop and have enabled it to spread over most of the plains and hills. It is not a coincidence that the most cultivated and valued Italian variety of walnut originated in Campania: it is the Sorrento cultivar, native to the Sorrento Peninsula where it has found a habitat with ideal environmental characteristics for the robust and harmonious development of the tree.

It has gradually spread from here to the classic fruit-farming areas of all the provinces of Campania (the majority with the suitable volcanic soil in the province of Naples), giving rise to a wide range of ecotypes, all known as the Sorrento Walnut, although there are two that are the most widely cultivated and marketed. There are two main types of Sorrento walnut which differ in shape: one has an elongated, regular and slightly pointed shell (the "pointed beard") at the top and rounded off at the base whilst the other is smaller and more rounded. The cultivation techniques, inspired by traditional growing methods, and the organoleptic character are the same for both types. In both cases the shell is light-coloured, not very wrinkled and thin enough to be broken with light pressure. The kernel - i.e. the edible part of the walnut - is cream coloured, not very oily, (though it can be preserved well for a certain period), substantial, soft and crunchy, with an extremely pleasant flavour and an unusual aroma and aftertaste, both when eaten fresh and after a period of preservation. The kernel also boasts a peculiar quality: unlike other types of walnut, it can be easily extracted whole, which makes it popular with the confectionery industry.

Cultivation of the Sorrento walnut in recent decades has gradually moved from its origin on the Sorrento coast (mainly the communes of Vico Equense and Monti Lattari) to the fertile areas of the Nolano-Palmese-Sarnese countryside, Campi Flegrei, Vesuvius, Vallo di Lauro e Baianese, Valle Caudina, as well as the Caserta Plain and the Irno Valley. The very first Sorrento walnuts are sold, still unripe, in Campania at the end of August and beginning of September, and they really are a speciality. The manual harvest is concentrated in the months of September and October, after which the walnuts are left to dry in the open, on trellises, in ventilated areas. The enviable qualities of this walnut make it an excellent ingredient for many recipes: it is delicious when eaten, for example, with home-made bread and the unripe walnuts are macerated in alcohol to make the famous Nocino, a dark, sweetly aromatic and digestive liqueur. The long-awaited IGP recognition (Protected Geographical Indication) is finally on its way for the excellent Sorrento Walnut, which is so appreciated by the market and has such close links with its traditional cultivation area. The Region has already started the preliminary studies for the production regulations and for all the documentation needed to apply for registration. This will help to protect and exploit this crop, which is more and more exposed to competition from foreign produce on the world market.