Târgu Ocna (Romanian pronunciation: [ˌtɨrɡu ˈokna]; Hungarian: Aknavásár) is a town in Bacău County, Romania.

The town is situated on the left bank of the Trotuș River, an affluent of the Siret, and on a branch railway which crosses the Ghimeș Pass from Moldavia into Transylvania.

Târgu Ocna is built among the Carpathian Mountains on bare hills formed of rock salt.

[3] In fact, the English translation of Ocna is salt mine.

Târgu Ocna's main industry is salt production, as it is the largest provider in Moldavia.