In La Salle, Valdigne, there is the parish of Derby, along the right bank of the Dora river. Over the years, it had maintained its own administrative autonomy (with its own mayor) and exercised its spiritual jurisdiction not only over the entire Envers area, but also over three villages in the Adret (Villaret, Les Champs and Equilivaz), which were also subject to the municipal administration of La Salle. In 1782, a decision of the Royale Délégation resolved the inevitable complications in the management of both temporal and religious affairs, establishing the definitive union of the two territories into a single municipality. Derby's documented history begins in 1040, when Umberto Biancamano, progenitor of the Savoy family and lord of Valdigne, donated two-thirds to the Cathedral Chapter and one-third to the Chapter of Sant'Orso of Aosta, as well as furniture and real estate of various kinds, the subjection on this territory. The name Delbia appears, for the first time, in this very act. A reminder of the importance of this territory are a number of significant testimonies along the main road through the town: the 'tower of justice', a fortified building dating back to the 16th century, which probably belonged to the Aosta Cathedral, the fortified house, also known as the 'tour des prisons', the jurisdictional seat of one of the two Chapters, the 16th-century house, presumably belonging to the noble Lachenal family. The parish, mentioned among the Valdostan parishes contained in the Pontifical of Blessed Emeric of Quart (early 14th century), is named capital of the Collegiate Church. In the capitular statutes of the Cathedral of 1477, the parish is instead documented as being owned by the Cathedral Chapter, which retained it until 1824, when it definitively relinquished its rights over the parish in favour of the bishop. The parish of Derby is placed under the protection of Saint Bear (a priest from Valle d'Aosta who lived between the 7th and 8th centuries, famous for his thaumaturgic powers) and Saint Blaise, bishop of Sebaste, Armenia, in the 4th century. The present, rectangular, single-nave building dates back to the 16th century and was consecrated by Bishop Ferragatta of Aosta on 22 July 1567. The altarpiece above the high altar (removed during restoration work), two marble twisted columns flanking the wall tabernacle, a large wooden triumphal arch crucifix (16th century, above the choir), and a small museum of sacred art, with a valuable 15th-century silver foil reliquary box, are of great importance. The bell tower, a slender and elegant square stone tower, dates back to 1416 and underwent major restoration in 1967.