TS25 Appropriate Technologies for Good Land Administration II – 3D Cadastre Mary Papaefthymiou, Tassos Labropoulos and Panagiotis Zentelis TS25.6 3-D Cadastre in Greece. Legal, Physical and Practical Issues. Application on Santorini Island FIG Working Week 2004 Athens, Greece, May 22-27, 2004 1/16 3-D Cadastre in Greece – Legal, Physical and Practical Issues Application on Santorini Island Mary PAPAEFTHYMIOU, Tassos LABROPOULOS and Panagiotis ZENTELIS, Greece Key words: 3-D Cadastre, registered rights, etc. SUMMARY A contemporary Cadastral system is used for the registration and management of information related to private or public properties. The usefulness of such a system varies, according to its structure, objective and automation level, but it is usually used to ensure and to protect property registered rights (based on certain secure procedures) and to constitute a tool for the development of many land or property related issues. Concerning the protection of rights, a Cadastral system involves registration and guarantee exclusively of any property standing on the surface of the earth. Every piece of Real Estate registered in the Cadastral system, is calculated as the sum of land plus developments (constructions) upon it. In other words, cadastral maps and cadastral charts represent just the level surface of the ground. Therefore, 3D reality is presented in a 2D way, making the Cadastral system itself “bi-dimensional”. Current evolutions in the social, technological and economical aspects of modern life require Cadastral systems with 3D enabled geometrical and topological models for property registration and description. 3 rd dimension should no longer constitute an element contained in a descriptive table, but an entity with a geometrical substance. Under these circumstances, proceeding to a 3D Cadastral system, is gradually necessary in short-term and absolutely essential in long-term. Referring to a 3D Cadastral system, does not necessarily involve an entirely 3D structured registration system. A compatible, able to incorporate 3D object registration, bi-dimensional system, can often do the job, with equal success. This project is aiming to prove, in which cases 3D visualization of reality is useful or even necessary to facilitate a mostly accurate and well-argued protection of (not-only surface) registered property rights. In this paper we can also find all the current cases in Greece, where using the 3 rd dimension is considered to be useful as well as necessary. Furthermore, an application of a 3D Cadastral registration process has been developed for a small village of Santorini island, called Castelli, located in Pyrgos community, from which typical examples are extracted. Finally, conclusions and suggestions are presented, in order to make the development of 3D Cadastral systems feasible when needed.