The Vardar (/ˈvɑːrdɑːr/; Macedonian: Вардарⓘ, Albanian: Vardar/-i, Turkish: Vardar) or Axios (Greek: Αξιός, romanized: Aksiós, Albanian: Asi (historically)[1]) is the longest river in North Macedonia and a major river in Greece, where it reaches the Aegean Sea at Thessaloniki.

It passes through Gostivar, Skopje and into Veles, crosses the Greek border near Gevgelija, Polykastro and Axioupoli ("town on the Axiós"), before emptying into the Aegean Sea in Central Macedonia, west of Thessaloniki in northern Greece.

The superhighways Greek National Road 1 in Greece and M1 and E75 run within the valley along the river's entire length to near Skopje.

[11] The Vardaris or Vardarec is a powerful prevailing northerly ravine wind which blows across the river valley in Greece as well as in North Macedonia.

When it encounters the high mountains that separate Greece from North Macedonia, it descends the other side, gathering a tremendous momentum and bringing cold conditions to the city of Thessaloniki and the Axios delta.

Somewhat similar to the mistral wind of France, it occurs when atmospheric pressure over eastern Europe is higher than over the Aegean Sea, as is often the case in winter.