Published by Maney Publishing (c) Survey Review Ltd VGI in Cadastre: a Greek experiment to investigate the potential of crowd sourcing techniques in Cadastral Mapping S. Basiouka* 1 and C. Potsiou 2 What make citizens participate in mapping projects? What motivates them to get involved in a non-hierarchical network of individuals who collect, edit and share geospatial data? Would they be willing to participate in cadastral mapping as an alternative way to speed up the cadastral survey and minimise the costs and errors which rise when traditional procedures allow limited owners’ participation? The answers are still ambiguous. However, it is a fact that the way geospatial data are used and the way citizens comprehend its importance have changed dramatically during the last years. The paper briefly gives an introduction on the evolution of Neogeography and the citizens’ involvement in spatial data collection, editing and uploading on the web, and of the introduction of the term volunteered geographic information (VGI) and its adoption by the scientific community. The paper then presents the first results of an academic research being compiled at NTUA in collaboration with FIG Com3 WG 3?2. focusing on the investigation of the potential for intergrading crowd sourcing techniques to create draft cadastral maps. The application area chosen for the experiment is the rural part of the village ‘Tsoukalades’, on the Greek island of Lefkada. Fifteen volunteer land owners participated to a weekend experiment and collected geospatial data for the delineation of their land parcel boundaries on a cadastral map; the spatial data were collected with the aid of a handheld GPS after a brief training; the resolutions from the interviews with the land owners and the resulting citizens’ cadastral map are presented. Keywords: Volunteered geographic information, Neogeography, Crowdsourcing, Cadastre Introduction The volunteered geographic information (VGI) was coined as a term by Goodchild [13] and was spread all over the world in a relatively short time. Its meaning is summarised by Sui [26] and others as ‘the digital spatial data which is collected and edited not by data producers but by citizens who are not experts but willing to disseminate their spatial knowledge and observations’ without any special invita- tion [25]. Blaut et al. [5] had earlier noticed the specific tension of all human beings to map by underling that all people have natural mapping abilities. In fact he predicted the evolution of mapping, the involvement of amateurs with the aid of web tools and the alteration of roles’ distribution between the mapping agencies and the users [6]. Many different terms were invested since then, however Elwood [10] was the first who differentiated them based on the content or the cartographic re- presentation. In the first category terms such as user generated content and collaboratively contributed geo- graphic information are included while in the second category terms such as ubiquitous cartography and web mapping are introduced. All these terms are parts of Neogeography [28] which constitute a general category including all the above. Neogeography ‘is about people using and creating their own maps, on their own terms and by combining elements of an existing toolset’ [28]. It is clear that although various terms are given to the phenomenon, the general meaning is the same and it is based on a ‘crowd sourcing’ philosophy. Many reasons contributed to VGI’s success. Affordable computer power, low cost of the equipment, widespread of broadband connection and dissemination of dynamic maps [21] are a few of them. Among the various tech- nological and economical aspects human reasons are also included. One of them can play a critical role in the creation of accurate cadastral maps: locality. Volunteered geographic information has cultivated this sense of locality. It is considered that no one knows the local area better than the residents. The whole project is 1 National Technical University of Athens, Athens, Greece 2 School of Rural & Surveying Engineering, National Technical University of Athens, Athens, Greece *Corresponding author, email s.basiouka@gmail.com ß 2012 Survey Review Ltd Received 19 December 2011; accepted 19 December 2011 DOI 10.1179/1752270611Y.0000000037 Survey Review 2012 VOL 44 NO 325 153