155 Georgios Lazarides Speleological research in the Loutra Arideas Area (Macedonia, Greece) Zusammenfassung: In dem vorliegenden Artikel werden die Karsthöhlen von Loutra Arideas (sogenannter „Speläologischer Park“) (Macedonia, Griechenland) vorgestellt und geologische Beobachtungen in Bezug auf ihre Entwicklung erstmals diskutiert. Der Schwerpunkt dieser Untersuchung liegt auf der Erforschung, Vermessung und Aufnahme aller bekannten Höhlen der Region. Abstract: In the present study the karstic caves of Loutra Arideas (so called „speleological park“) (Macedonia, Greece) are presented and geological observations in relation to their speleogenesis are preliminarily discussed. This research is focused on the exploration, mapping and recording of all the known caves of the area. Résumé: L’article présente les grottes de Loutra Arideas („Parc spéléologique“) en Macédoine (Grèce) et les observations géologiques préliminaires en relation avec leur genèse. Ces recherches sont focussées sur l’exploration, la cartographie et le relevé de toutes les grottes connues dans la région. Key words: Loutra Arideas (Macedonia, Greece), speleological research Introduction The Loutra Arideas region is located in Almopia basin, in Northern Greece (Macedonia), 120km north-west of Thessaloniki and 2km from the Loutraki village (fig. 1). The site administratively belongs to Municipality of Aridea, Prefecture of Pella. A system of caves (figs. 2, 3) has been developed mainly in the northern side of the V-shaped gorge of Nicolaou stream (fig. 4a), on the slopes of the Voras Mt (2524m) that is one of the highest mountains of Greece, very close to the former Yugoslavian border. The broader area is situated near the geological boundary between Almopia zone to the east and Pelagonian zone to the west (MERCIER 1968, MOUNTRAKIS 1976). It consists of Mesozoic metamorphic and sedimentary rocks, and more precisely the gorge of the Nicolaou stream consists of Maastrichtian Neue Forschungen zum Höhlenbären in Europa Abhandlung Band 45/2005 ISSN 0077-6149 Seite 155-162 Naturhistorische Gesellschaft Nürnberg e.V. Marientorgraben 8, 90402 Nürnberg