Located along the Bulgarian - Greek border the Rhodope Mountains cover an area of 18 000 km², still 80% of their territory, 14 737 km² falls into the boundaries of Bulgaria. Being part of the large Macedonian - Tracian Mountain Massif the Rhodopes Mountains are geographically divided to two parts - the Western and the Eastern Rhodopes.
       For thousands of years the local population in the Rhodope Mountains have lived in harmony and understanding with the surrounding nature. This has allowed the preservation of an astonishing richness and variety of flora and fauna species there.
       Although complete inventory of the Rhodopean flora does not exist yet, it is expected that the number of the vacuolar plants occurring in the Rhodopes Mountains is some 2 250. These present 46.7% of the whole Bulgarian floral gene pool. Speaking about the mountain, it is worth mentioning that three of the most potent species formation centres are located there - 11% of the plants occurring in the Rhodopes are endemics and 226 flora species enlisted in the Bulgarian Red Data Book. Numerous beautiful flowers - local endemic species are named after the Rhodopes - the most famous of them - Haberlea rhodopaensis is the symbol of the mountains.
       The forest in the Rhodope Mountains present approximately 23% of the total for the country. Extremely valuable are the huge coniferous massif of Boreal type survived there - the larges in Europe, apart from the European taiga. A great percentage of them are either natural or primary ones. The highest is the distribution of the Scotch pine forests, followed by the Norway spruce and the European beach ones. The abundance of endemic Macedonian pine and the Australian pine there is also notable.
       The fauna of the two parts matches significant difference - Western Rhodopes are characterized with the occurrence of the Euro-Siberian and the European species, while in the Eastern Rhodopes the fauna is under the strong influence of the Mediterranean elements.
       About 50 of the vertebrates, breeding in the Rhodopes, deserve special conservation attention. Some of them are already included into the Bulgarian or the World Red Data Books or appear in Appendix II of the Bern Convention. Among the mammals could be counted the bear, the wolf, the otter, the marbled polecat, the Balkan chamois, the mouse tailed dormouse and several bat species.
       The Eastern Rhodopes, on both the Bulgarian and Greek side are among the most important birds of prey area in Europe. A variety of birds, with European or global conservational importance are known to be breeding there, such are the black stork, the black vulture, the griffon vulture, the Egyptian vulture, the imperial eagle, the Levant sparrow hawk, the sacker falcon etc. 73 of the birds occurring in the Rhodopes are enlisted in the Bulgarian Red Data Book and 10 of those are globally threatened.
       The region of the Rhodopes is also rich in reptiles and amphibians. It is especially true for the Eastern Part where species like the pond turtle, the slender glass lizard, the snake-eyed lizard, the sand boa, and the glacial relict - Alpine newt are breeding.
       Given all this variety and richness of the biota in the Rhodopes, it is to be admitted that the existing protected areas there is not quite sufficient to assure the long-term preservation of this amazing nature. Yet the 18 strict reserves and 23 protected sites are a good basis for the development of large-scale nature park, where the sustained development concept could be implemented.
       With the present population of some 680 000 the Rhodopes are the most heavily populated mountain in Bulgaria. Considering this fact, as well as the historical traditions in the reasonable utilization of the natural resources of the local people, the integration of the conservation and the environmentally friendly development of the whole region seems both reachable and promising prospective to the effective and efficient preservation of the unique historical, cultural and natural heritage for the benefit of the future generation.
       The Rhodope Mountains are one of the most beautiful mountains on the Balkan Peninsula. The highest peak is Golyam Perelik - 2149m, followed by Persenk.
       Geographically three types of rocks form the Rhodopes:

       The carbonate rocks together with the litho-tectonic and physic-geographic conditions are a prerequisite for the development of different surface and ground layers.
       The Karst in the Rhodopes is isolated in seven karst regions, explored in over 700 caves and abysses. One can find here the longest and the deepest abysses in Bulgaria. Traces of long extinct fauna species have been found in these caves - Pleistocene vertebrate fauna, prehistoric findings from the stone-copper age, i.e. V-IV millennium B.C. original caves fauna with new animal species for the World.
       The history of speleoexploration in the Rhodopes can be divided in two periods:
First Period - time of unorganized speleoexplorations in the period between 1900-1940.
Second Period - from 1950 to present days, period of organized purposeful investigations. The chief organizer of these is Dimiter Raitchev who organized a special speleological activities center in 1950, which in turn grew into a speleoclub in 1962.
       The speleoexplorations in the different regions of the Rhodopes are aimed in the following fields: