Petrified forest, Agia Marina, Agios Nikolaos Geopark, beach with turquoise water in the south of Greece, Greece

agia marina agios nikolaos geopark beach turquoise water southern greece petrified forest rocky shore coastal landscape nature holidays travel relaxation summer scenic clear geology flora fauna outdoor activities tranquility vacation sunbathing swimming geological formations marine life hidden gems bay picturesque views snorkeling crystal erosion unique adventure hiking cliffside sandy exploration