Greece has been generously blessed with nature. Mountains, olive groves, caves, caves driven into the sea - there are plenty of natural gems. The most recognizable ones are the Blue Grottoes and the Shipwreck Bay in Zakynthos . In addition, it is worth visiting the Mount Olympus National Park on the Olympic Riviera, the area of Rethymno in Crete with the most beautiful cave on the island and the largest marine park in Europe, covering, among others, the islet of Alonissos.