The Hron (Slovak: Hron; German: Gran; Hungarian: Garam; Latin: Granus) is a 271-kilometre (168 mi) long left tributary of the Danube[1] and the second-longest river in Slovakia.

It flows from its source in the Low Tatra Mountains (below Kráľova hoľa) through central and southern Slovakia, emptying into the Danube near Štúrovo and Esztergom.

Major cities and towns on the Hron are Brezno, Banská Bystrica, Sliač, Zvolen, Žiar nad Hronom, Žarnovica, Nová Baňa, Tlmače, Levice, Želiezovce, and Štúrovo.

The river's basin covers 5,465 km2 (2,110 sq mi),[1] which is approximately 11 percent of Slovakia's territory.

The name is probably of Germanic origin; *Granahua: gran – spruce, ahua – water.