The municipality of Sittard-Geleen came into existence in 2001 out of the union of Sittard, Geleen and Born. The current municipality's area contains eight formerly independent municipalities. The archives of these former municipalities are held by the Sittard-Geleen City Archive. Non-government archives have also been stored here: archives of parishes and association, and collections of local celebrities. They include the literary collections of Felix Rutten, Jacques Schreurs and Charles Beltjens.

The City Archive has a vast library on the region's history at its disposal. The large image collection (photographs, negatives, picture postcards, slides) is currently being digitised and will be accessible via the Internet in the near future.