Downe Activity Centre is an 86-acre outdoor facility in the London Borough of Bromley, near Orpington in Greater London, situated close to Biggin Hill airfield.

Originally established as a Scout camp in 1929, it is now operated by the Friends of Downe Activity Centre and continues to serve Scouts, Guides, schools, and other groups.

The site encompasses a mix of ancient woodland and open grassland, offering both camping and indoor accommodation. Indoor blocks include kitchen facilities, bunkrooms, halls, and showers.

The varied terrain supports a range of outdoor activities, and the centre is accessible from Orpington and Chelsfield railway stations, roughly 16 miles from central London.