Bolyarovo municipality is located in one of the cleanest regions of the country – the southern part of Yambol Province, on the northern parts of Strandzha mountain. The municipality covers parts of the Tundzha hills, the Derventski hills and the southern part of the Bakadzhiks.
The old name of Bolyarovo is Pashakyoy. The place is very old and there are evidences of Thracian settlements near the villages of Kraynovo, Iglika, Popovo, Dennitsa and Kamen Vrah (Stone Peak). There are also evidences of copper works near the Trofalishki holes. It was an important main road in the past as it was connecting the town of Odrin with parts of Bulgaria.
An ottoman fortress, which is believed to be built by Khan Omurtag, and another fortress, named Potamucastel were found during archeological excavation near the village of Voden. In the Eski Dzhumaya region, which is one kilometer from Dennitsa village, there are evidences of a medieval village. The three fortresses near Voden were very important in medieval Bulgaria.
One of the most interesting places in the municipality, and also in the whole region, is the dam “Malko Sharkovo”. It is located near the village of Malko Sharkovo in Strandzha mountain, close to the border with Turkey. In 1989 the territory around the dam wass announced as very important for the ornithological biodiversity by BirdLife International. The territory is a hot biodiversity spot and there 45 bird species can be found, from which 16 are included in the Red Data Book of Europe and Bulgaria. Some of the bird species that spend the winter there are greater white-fronted goose, mute swan, whooper swan, red-breasted goose and many other unique bird species. The dam is a very popular place for ecotourism.