At about a third of the way down the western shore of Kassandra, Siviri, on the Gulf of Thermi, is 9 km, and just across the peninsula, from Kallithea, on the Bay of Toroneaos. There is a small stream that flows during the rainy season in the late winter which splits the village in half and empties out into the gulf.
The beach at Siviri is very nice; the sand is white and fine, and the waters of the Gulf are sparklingly translucent. The beach is organized, with umbrellas and sun beds, and there are beach rentals right on the water. As with all locations on Kassandra's west coast, Mt. Olympus is visible, some 75 km across the bay. A couple kilometers up the coast is the Elani Bay resort, if your thing is resorts, rather than villages.
Siviri is pretty heavily tilted toward meeting the needs of the tourist trade, and you'll find a lot of Greeks as well as non-Greeks spending their holiday there.
Siviri is home to the Festival of Kassandra, an ongoing summer event which usually runs during the months of July and August. Cinema, along with performances in music, song, dance, and theatre, are held during the festival at the Siviri outdoor amphitheatre. Performers in the festival are both from the international community and from Greece.
Some recent productions have been The Wizard of Oz, the musical "I Am What I Am," by Takis Zaxaratos, Aristophanes' The Clouds, plus concerts by some of Greece's best-known contemporary singers.