Ådal is a valley located in the municipality of Ringerike in Buskerud County, Norway. It was also a former municipality in its own right before being incorporated into Ringerike.

The municipality was created in 1857 by a split from Norderhov. At that time Ådal had a population of 2,382. On 1 January 1964 Ådal was merged with Hønefoss, Tyristrand, Hole and Norderhov to form the new municipality Ringerike. Prior to the merger Ådal had a population of 3,442.^[1]

Traditionally the Ådal parish has been divided three ways. Ytre Ådal includes the village of Hallingby and is the site of Hallingby school and Hval Church (Hval kirke). Øvre Ådal includes the village of Nes, Ådal and is the site of Nes school, Ringmoen school and Nes Church (Nes kirke). Vestre Ådal is the site of Viker Church and the Ådal Mountains (Ådalsfjellene), a small mountain range which stretches from Ådal to Vassfarfoten on the border with Vassfaret and Sør-Aurdal in Oppland.

Sperillen, the 33rd largest lake in Norway, is located in Ådal. The rivers Begna (from Begnadalen) and Urula (from Hedalen) flow into the lake from the north. At the south end of the lake, there is a dam located near Ringmoen. The lake is well known for its fisheries and is one of the few within Norway with a commercial fishery.

The first church in Ådal was a stave church constructed during the 15th century, as documented in the Diplomatarium Norvegicum in 1462. Prior to the 17th century, it was affiliated with Hole, and later, following the Protestant Reformation, it became part of the Norderhov parish. By 1700, due to the increasing needs of its parish, Ådal required a new church to accommodate its growing population.^[2]

Viker Church (Norwegian: Viker Kirke) is situated on the western shore of Sperillen Lake. Built in 1702, the church retains elements from the old Stave church, including the pulpit, altar, and crucifixes. Its interior features open ceilings and oiled wood walls, while the exterior boasts a dark brown wooden facade. The altarpiece dates back to the 1720s, and the baptismal font, with its octagonal top and bottom, was crafted in 1728. The church tower houses two bells, one dating to 1721 and the other to 1842. Due to its location amidst a forested area, Viker Church is somewhat challenging to spot from a distance.^[3]

TheOld Norsename of the district wasÁrdalr. The first element is the genitive case ofáfor ‘river’, the last element isdalrmeaning ‘dale or valley’.