Purpose: The purpose of this paper is to describe a project to digitise maps at the Royal Tropical Institute, or Koninklijk Instituut voor de Tropen (KIT), of The Netherlands. KIT has an extensive collection of maps and nautical charts of (sub-) tropical regions, including general maps and topographical map series, city maps, thematic maps and national atlases. The collection comprises some 27,000 maps and over 1,000 atlases. Almost 12,000 maps are from the former Dutch colonies, Netherlands Indies (Indonesia), Surinam and The Netherlands Antilles. Design/methodology/approach: The paper explains how users have access to the maps via the Library's online catalogue. One of the future goals is combining the KIT collections in order to make it possible to search a map and to find accompanying documents, museum objects and photographs and to add more metadata. Findings: The paper finds that the digitised collection of maps has been used by various researchers as well as by relief workers in the aftermath of the tsunami in Indonesia. Originality/value: The innovative part of the project is the ability to search by location and to navigate through serial maps. A link with Google Earth makes it possible to compare an old map with a new satellite image. (Contains 4 figures.)