Abstract: The old cadastral maps of the Spanish General Directorate for Cadastre (DGC) have always been in great demand. It was decided in 2012 to make an initial inventory of these maps with the type of information available, physical location,and condition. Subsequently,to evaluate their possible use,the inventory was examined to investigate whether these maps could be geographically referenced and made available on a geoportal. Several years later,it was determined that the inventory needed to be updated with a series of improvements (expanding the fields so that they become clearer,homogeneous,and more easily handled by software). A questionnaire was issued to technical specialists on property boundaries. As a principal conclusion we can highlight that the use of old cadastral maps in Spain is of great importance. The information on these maps is widely demanded by technical and legal experts who consider that
an update and revision of the DGC inventory is essential. It is crucial that old cadastral maps are digitised and made available online,preferably free of charge and through an easy-to-use geoportal. The information on these maps helps to resolve property boundary disputes and has many other uses. Investment in the economic and human resources needed to preserve and publish these maps is essential given their great value.

Key words: cadastre, 　old maps, 　cartography, 　demarcation of property, 　historical maps, 　geoportal