Slanec (German: Salzburg; Hungarian: Nagyszalánc; Latin: Castrum Salis) is a village and municipality in Košice-okolie District in the Košice Region of eastern Slovakia.

In historical records the village was first mentioned in 1230 (Castrum Salis) as an important fortress.

In 1270 King Stephen V of Hungary gave the castle to Master Reinhold.

In 1299 the castle passed to the Szalanczyi noble family and, successively, to landowners by the surnames of Lossonczy and Forgách.

The village lies at an altitude of 345 metres and covers an area of 20.459 km².