Sani sits on the upper west coast of Kassandra, where a long curve of fine sand meets a small, marshy wetland and a marina full of yachts. The beach is reliably calm and family-friendly; the wetland behind it is a Natura 2000 site and a good spot for birdwatching, especially during spring and autumn migrations.
A short walk from the beach is the Byzantine Stavronikita Tower, restored and now used for summer concerts and events as part of the long-running Sani Festival. The area is dominated by an upmarket resort, but the beach itself is public and worth visiting even if you are staying elsewhere on Halkidiki.