It’s a style of music developed in isolation in Eastern Europe.

Now the music of Bulgaria is coming to central and coastal Maine, care of the Bisserov Sisters, one of that country’s national treasures.

The sisters – Lyubinka, Neda and Mitra – are making their first tour of the United States, thanks, in large part, to the efforts of the 20-member Maine Women’s Balkan Choir.

The Bisserovs will perform in concert at 9 p.m. Wednesday, Oct. 9, at the Rockport Opera House, at 7:30 p.m. Thursday, Oct. 10, at Minsky Auditorium, University of Maine, Orono; and at 7:30 p.m. Saturday, Oct. 12, at College of the Atlantic, Bar Harbor. The sisters and their four-member band also will be holding voice and instrumental workshops today in Camden and Saturday and Sunday at the Trenton Grange (preregistration is required).

The sisters were born in a village high in the Pirin Mountains of Bulgaria, near the borders of Macedonia and Greece. They learned the women’s songs of the region singing with relatives and on special occasions.

In 1978, the Bisserov Sisters made their official debut at the 11th World Folk Festival in Cuba, taking first prize in the competition. They have since expanded their ensemble to include their sons, who accompany them on traditional instruments, and their daughters, who join in the singing.

This tour indirectly had its origin a decade ago, when Bar Harbor resident Kirsten Stockman, now the Maine choir’s director, walked into a room where Balkan music was playing.

“I loved it; it went straight to my heart,” Stockman recalled.

Bulgarian music is quite different from that of the West.

“It’s in minor keys usually,” Stockman explained. “It’s played in really fast meters, some that Western musicians can’t even grasp. The singing tradition in Bulgaria developed a unique style in isolation, without outside influences. It’s got a haunting, melancholy sound.”

Stockman found a group of women similarly fond of the music of the Balkans, and they formed the Maine Women’s Balkan Choir about three years ago.

Stockman traveled to Bulgaria a year ago, to hear the music in its natural setting.

“It was so astounding hearing it live,” she recalled. “The [Bisserovs] were so warm, and the people were so amazing. We wanted to give something back to them, because we’ve so enjoyed doing their music.”

Stockman had this crazy idea of bringing the Bisserovs to America, and her choir mates joined in. Through a series of concerts and donations, the choir reached its monetary goal by August. Also Stockman reached out to her contacts, who in turn talked to others, until, when all was said and done, the Bisserov Sisters were coming for a 25-stop tour over a six-week period, which began Sept. 24 in Chicago.

“All these different people who had met the Bisserovs arranged concerts in their cities,” Stockman said. “It wasn’t hard to convince people to host the Bisserovs. Still, it was a lot bigger tour than I had thought possible.”

Stockman is thrilled by what her group has managed, and is eagerly awaiting the Bisserovs’ stop in Maine.

“I can’t believe we accomplished this,” she said. “They’re actually here.”

For more information or to register for workshops, call Kirsten Stockman at 288-3800 or e-mail kstock@gwi.net.