Hi. The second "leg" of Halkidiki is called Sithonia. Sithonia is surrounded by the bays of Toroneos and Singitikos. The beautiful forests of Sithonia overlook the sea waves from the mountain ranges. The highest peak, Itamos, is 811 meters above sea level. According to the legend, it is in the emerald grove of Sithonia that the god of the underworld Hades was able to trap the beautiful Persephone https://holidaygreece.eu/sitoniia/g.3. The name of the peninsula comes from the titan Sithon, son of Poseidon. But to learn more about this "leg" I recommend this site