Bayani: Bacan (Dutch: Batjan), wanda aka fi sani da Bachian ko Batchian, ita ce tsibiri mafi girma a cikin rukunin. Tsibiri na biyu da na uku mafi girma sune Kasiruta da Mandioli. Bacan ya ƙunshi kusan mutane 60,000 wanda kusan 8,000 ke zaune a babban birnin Labuha; an raba shi zuwa gundumomi 7. Kasiruta da Mandioli kowannensu yana da mazauna sama da 8,000, kuma kowannensu an raba shi zuwa gundumomi 2. Akwai ƙananan tsibirai da yawa a cikin rukunin. Tambaya: Waɗanne tsibirai biyu ne suka fi Bacan girma?
Kasiruta da Mandioli