The original main entrance to the castle is located to the west, in the direction of the city of Aosta, and is easily recognisable by the monumentality of the portal bearing the Gamba family coat of arms and the year 1901, the start date of construction work, which would continue until 1903 (the year engraved on the north front of the building). The charm of this residence is further amplified by the large park surrounding it, whose 50 hectares also feature rare, exotic and large species. The design of the entire complex, which also includes the stables and the caretaker's house, visible along the path that visitors take when entering the park to reach the current entrance to the castle, the elevated terrace with fishpond, the retaining wall, the stairs and the paths to access it, is thanks to the engineer Carlo Saroldi of Turin. Carlo Maurizio Gamba and Angélique Passerin d'Entrèves, however, would only enjoy their residence in Châtillon for a few years. Angélique died in 1909, after the loss of her daughter Irene at an early age, and on the death of Carlo Maurizio in 1928, in the absence of heirs, Gamba Castle passed to the Passerin d'Entrèves family, in the person of Count Hector.
Purchased by the Region of the Valle d'Aosta and reconverted to public use with a museum function after a period of abandonment, since 2012 the Gamba Castle has opened its doors to the discovery of the regional collections of modern and contemporary art, a numerically consistent patrimony that is also characterised by the presence of a copious photographic collection. Collected since the mid-twentieth century and in constant expansion, the works of art stored at Gamba cover a chronological span from the 19th century, through the 20th century, and up to the 2000s, to include works by living artists.
Today, the surroundings of the castle also host the works of the regional collection, or become a place to host site-specific temporary installations, as has often been the case for the fishpond, as well as opening up glimpses and placed viewpoints on the Valley with a strong visual impact, in a very close union between art and landscape.
Moreover, since 21 July 2022, Gamba Castle has changed its face thanks to the permanent installation of the work 'Orbita', by Massimo Uberti. It is an ellipse of light conceived by the artist that embraces the central tower of the castle, making it not only visible from far away, but also giving it a different and special identity: the Contemporary centre of the Aosta Valley.
