The closest activity to Nikiti (Sithonia) is Stroll in Old Nikiti, just 450 m away. Ordered by distance from Nikiti. Info, prices, booking.
450 m from Nikiti

9.7 km from Nikiti

15.5 km from Nikiti

16.6 km from Nikiti

29.9 km from Nikiti

30.0 km from Nikiti

30.8 km from Nikiti

31.3 km from Nikiti

32.2 km from Nikiti
Stroll in Old Nikiti, just 450 m from Nikiti. The rest are listed below, ordered by distance.
Within 15 km of Nikiti there are 3 activities, with 10 across Sithonia in total.
Based on user reviews: Cycling Route of Sithonia (★5.0), Boat Trip to Diaporos (★4.9), Sailing in Neos Marmaras (★4.9).
The activities are spread out around Nikiti. A car makes exploring much easier — local buses and taxis are limited outside peak season.
Nikiti 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.