The name derives from the Latin name "Manius. A municipality in the province of Asti, located on the border with the province of Alessandria, near the valleys crossed by the river Rio Gaminella and stream Grana, Montemagno is characterized by the presence of twelve separate narrow street lanes that all feature Roman numerals and are dominated by the impressive bulk of the castle. Departure point for memorable excursions, the surrounding area offers trekking itineraries that feature spectacular views and a soak into the local history. The town is also famous for its highly appreciated wines, such as: Chardonnay and Barbera.
Founded around the year 1000, the town lies on a hill, built around its fortress that, over the centuries, was transformed into a mighty castle with battlements built to protect the heart of each representative street, between itself and the surrounding fortified walls of the old main centre.
The town was granted in fief to the Marquis of Monferrato. It's history is marked by struggles between Guelphs and Ghibellines with Asti and Alessandria. In the first half of the XV century, the Marquis of Monferrato allied with the Savoy and for this reason, Montemagno experienced several raids by Spanish, French and German. In the early XVII century it became fief of the Ardizzi and later was ceded to Giovanni Gallone, later to the Callori of Vignale, to which the restoration of the castle is attributed. The last feudal Lord of Montemagno was Ottavio Grisella.

Not to miss:
- the Parish Church of San Martino and Santa Maria Assunta with its nearby square and its Baroque staircase in Cumiana stone, which recalls the famous Spanish Steps in Rome. The origins are ancient, but it has been renovated several times and today houses a valuable painting by Pier Francesco Guala;
- the Church of Our Lady of Vallina, located in the middle of a valley surrounded by hills and has XIX century origins;
- the remains of the Church of Saints Vittore and Corona, located near to the cemetery, built in the XI century in Romanesque style. It features a very distinctive Bell tower with mullioned windows that open onto the belfry. It has recently been renovated and from its privileged location, situated on a hill, it is possible to enjoy a picturesque view of the entire Basso Monferrato with its orderly lined vineyards that adorn the surrounding hills;
- the Church of Santa Maria della Cava, located on the outskirts of town, onside it preserves an important collection of frescoes;
- the Church entitled to the Trinity with a splendid Baroque façade;
- the Church of the Confraternity of St. Michael dating from the XVIII century;
- the Castle, of medieval origin, is a sturdy building renovated several times, today a private residence surrounded by a park;
- La Casa sul Portone, the last remaining medieval entrance gateway between the walls, probably built in the XIV century.