"Macedonia" airport (SKG) is the main gateway to Halkidiki, just 60-120 minutes by car.
Highway → Ring road → Thessaloniki-Halkidiki road. Roads in excellent condition.
~400 km / 4-5 hours via Promachonas border → Serres → Thessaloniki.
~700 km / 8-9 hours via Bulgaria.
~600 km / 6-7 hours via Niš → Skopje → Thessaloniki.
Private transfers from airport: €60-100 depending on destination.
Highly recommended. Halkidiki lacks full public transport. A car lets you discover hidden beaches and villages.