Sint-Genesius-Rode in the context of Watermael-Boitsfort

Uccle (French, pronounced [ykl(ə)] ) or Ukkel (Dutch, pronounced [ˈʏkəl] ) is one of the 19 municipalities of the Brussels-Capital Region, Belgium. Located in the southern part of the region, it is bordered by the City of Brussels, Forest, Ixelles, and Watermael-Boitsfort, as well as the Flemish municipalities of Drogenbos, Linkebeek and Sint-Genesius-Rode. In common with all of Brussels' municipalities, it is legally bilingual (French–Dutch).

As of 1 January 2022, the municipality had a population of 85,099 inhabitants. The total area is 22.87 km (8.83 sq mi), which gives a population density of 3,720/km (9,600/sq mi), half the average of Brussels. It is generally considered an affluent area of the region, and is particularly noted for its community of French immigrants.

The Sonian Forest or Sonian Wood (Dutch: Zoniënwoud, pronounced [ˈzoːnijə(ɱ)ʋʌut]; French: Forêt de Soignes, pronounced [fɔ.ʁɛ d(ə) swaɲ]) is a 4,421-hectare (10,920-acre) forest at the south-eastern edge of Brussels, Belgium. It is connected to the Bois de la Cambre/Ter Kamerenbos, an urban public park which enters the city up to 4 kilometres (2.5 mi) from the city centre.

The forest lies in the Flemish municipalities of Sint-Genesius-Rode, Hoeilaart, Overijse, and Tervuren, in the Brussels-Capital Region municipalities of Uccle, Watermael-Boitsfort, Auderghem, and Woluwe-Saint-Pierre, and in the Walloon towns of La Hulpe and Waterloo. Thus, it stretches out over the three Belgian Regions. It is maintained by Flanders (56%), Brussels (38%), and Wallonia (6%). There are some contiguous tracts of privately held forest and the Kapucijnenbos, the "Capuchin Wood", which belongs to the Royal Trust.