The closest beach to Elia (Sithonia) is Anthemo Beach, just 360 m away. Within 15 km there are 32 beaches; below are the 12 closest to Elia, ordered by distance. Photos, map, reviews.
360 m from Elia

610 m from Elia

1.7 km from Elia

3.2 km from Elia

3.2 km from Elia

4.1 km from Elia

4.8 km from Elia

5.7 km from Elia

6.4 km from Elia

6.5 km from Elia

6.8 km from Elia

Anthemo Beach, just 360 m from Elia. The rest are listed below, ordered by distance.
Within 15 km of Elia there are 32 beaches, with 69 across Sithonia in total.
Based on user reviews: Karydi (★4.3), Lagomandra Beach (★3.8), Castello Beach (★3.8).
The beaches are spread out around Elia. A car makes exploring much easier — local buses and taxis are limited outside peak season.
Elia is on the Sithonia side of Halkidiki, in northern Greece. The nearest airport is Thessaloniki (SKG); from there a car is the most convenient way to reach the Sithonia villages.