The Spring of Žagubica, popularly known as Mlava spring, is located in the southeastern part of the Žagubica valley, at the foot of the northern edges of Beljanica mountain with an altitude of 312 m. This spring resembles a small lake which actually represents a submerged sinkhole surrounded by the spring’s mountain slopes and a hill called “Kondžilo”.
When they first measured the depth of the spring, it was 24 m. Later, a Serbian diver, Uroš Aksamović, managed to reach 72 m of its depth. The members of the diving club “Triton” from Belgrade, Vladimir Taleski and Mirko Bevenja, have reached 84 m of its depth, in July 2008. It is certain that this is not the final depth, namely, it is assumed that the spring is quite deeper. Since it arises from the siphon channels under high pressure, the accurate measurement is disenabled. The water of Žagubica spring is sometimes green, sometimes dark green. The reason behind its color is the presence of algae found in shallower parts of the spring, but also the greenery which surrounds it. The water becomes turbid during the spring period when the snow from Beljanica melts and also during rainy periods. The amount of water of the spring depends on the atmospheric sediment which is extracted and the snow break on Beljanica. Fishing is forbidden. The spring abounds in the famous Mlava trout which is quite an attraction for the tourists. A complete drying up of the spring and the cessation of its functioning have been documented. Our famous geographer, Jovan Cvijić, was the first eyewitness to this phenomenon in 1893. The phenomenon of drying up of the spring is caused by clogging the narrowed parts of the underground canals. When the power of the accumulated water overcomes the clogging, the water flows from the spring again. Žagubica spring represents an amiable holiday ambience and is the main tourist attraction in Žagubica Municipality. The beauty and attraction of this spring are complemented by the greenery of the environment and the beautifully arranged stream of the spring. The reflection of the motel “Vrelo” can be seen in the crystal clear and clean water. Since Mlava spring is only one kilometer away from the center of Žagubica, it has a great advantage in terms of tourism development. Those who come to Žagubica inevitably visit the Spring of Mlava in order to admire its splendidness. In order to preserve this natural beauty, Mlava spring and its environment were put under state protection, for the first time in 1979, as a valuable hydrological natural monument of the first category. Mlava Spring was declared a natural monument in 1995 by a decree of the Government of the Republic of Serbia.