Čvrsnica mountain lies between the Neretva canyon in the east, Dugo Field in the west, Doljanka in the north and Drežanka in the south. The highest peak, Pločno, 2,228 meters above sea level. Čvrsnica consists of a set of several plateaus and ridges, which are separated by deep valleys of the Neretva’s tributaries.
Plateaus of Plasa with Muharnica and Mala Čvrsnica are in the north and south, and between them there are Vilinac and Velika Čvrsnica ridges rising from the vast plain.
Plasa is located in the northeastern part of Čvrsnica and lies between the valleys of Doljanka, Neretva and Grabovica, into which its steep cliffs descend. It was built from Jurassic limestone and is divided into the lower Gvozd and the higher Prava Plasa.
Gvozd is a cove with many small sinkholes, two kilometers wide and overgrown with beech and pine forest, in contrast to Prava Plasa, which is bare and with larger sinkholes. Prava Plasa has several elevations, the most prominent of which is Plasa at 1,577 meters above sea level.
The locality of Plasa can be reached from Diva Grabovica, which is reached by the road from Jablanica towards Mostar. After the Begić and Begović bridge, it is necessary to turn right across Neretva and drive on the macadam road to the destination. At the end of the road there is an extension where you can park your car.
The ascent from Diva Grabovica along the former forest path to the Plasa plateau takes three hours. It starts like the path to Žlijeb via the Begovića fountain, but at the intersection of Nevaj it separates and crosses Plaski potok, passes by the spring under Tučko brdo, crosses Strmenički stream, climbs along the serpentine path.
Then there is a steep ascent with serpentines over the remains of the hunting house or Ivanković’s habitat above which there is a hot spring, and it emerges on the Plasa plateau. There is the mountain house Plasa where you can rest or spend the night.