The set of 6 bronze bells has made music for the city center over the past 135 years
The cathedral has six bronze bells weighing a total of 30 metric tons which are designed so that each plays one of the six notes do, re, mi, sol, la, and si.
The la and si bells in the left tower.
The bells are between 1.65 and 8.8 tons in weight, 1.25 and 3.5 in diameters.
Each has a different carving pattern.
Like all other parts of the cathedral, the bells were made in France, in 1879.
A French tourist once said that many churches in France would feel envy for not having a similar bell set, according to priests at the cathedral.
Each bell is attached to an independent scaffolding structure for safety reasons.
The priests said they only ring all six bells at once on special occasions.
The bells are power-operated and the sound can be heard from up to 10 kilometers away.
One has to use steep rock, iron and wooden stairs to climb up to the bell towers.
From the tower, one can have a great view of the city. The bells were nearly 37 meters above the ground at the beginning, until an architect added two conic towers to the cathedral and raised them to more than 60 meters in 1895.
The priests are having the church restored for the first time after 135 years to fix some damaged parts, including the rusted iron roofing and broken doors of the bell towers.