Drežnica Valley or Drežanka Canyon is a valley surrounding a mountain stream Drežanka, which cuts through a deep 29 kilometers long karstic gorge between mountains Čvrsnica and Čabulja, part of the Dinaric Alps range. The stream is right tributary of the Neretva, and a valley follows the west-east axes. The main settlements are Gornja Drežnica and Donja Drežnica with their numerous hamlets, and are part of the territory of the city of Mostar, in Bosnia and Herzegovina.