Abujmarh (Abujhmar) is a hilly forest area, spread over 1,500 square miles (3,900 km2) in Chhattisgarh, covering Narayanpur district, Bijapur district and Dantewada district. It is home to indigenous tribes of India, including Gond, Muria, Abuj Maria, and Halbaas. It was only in 2009 that the Government of Chhattisgarh lifted the restriction on the entry of common people in the area imposed in the early 1980s. Geographically isolated and largely inaccessible, the area continues to show no physical presence of the civil administration, and is also known as "liberated-zone" as it is an alleged hub of Naxalite-Maoist insurgency, the banned Communist Party of India (Maoist) and its military wing, People's Liberation Guerilla Army (PLGA), who run a parallel government in the area.
In 2007 the area was proposed as a biosphere reserve by Ministry of Environment and Forests, Government of India.
The word, Abujmarh means "the unknown hills" ("abuj" means "unknown" and "Marh" meand "hill) in the Gondi language native to the region.
Abujmarh hills are the part of the much larger Dandakaranya forest, about 35,600 square miles (92,200 km2) equivalent to the present Bastar division. Dandakaranya, literally meaning "the abode of the demon Dandaka", also finds mention in Hindu epic, Ramayana.
The dense forests of Abujmarh have long been isolated from the outside world, inhabited largely the indigenous people, and accessible only via forest pathways starting from Narayanpur, Bijapur and Basroor. Geographically, the Indravati river segregates it from Bastar region, adding to its isolation. Recently the access to area has been further marred by heavy use of landmines by the insurgents at entry points. During the British rule in India, Abujmarh remained in isolation and constitutionally "excluded", though a land survey was done in 1873. After independence of India, its isolation continued, except when in 1958 the government refugees from East Bengal in the Dandakaranya area in the present Bastar division, and later the hills started getting exploited for its mineral wealth, like the Bailadila Hills excavated for its deposits of high-grade iron ore. The tribals remained backward and exploited by prevalent feudalism in India, majority of them started cultivation only recently, and education was undertaken only at small schools run either by NGOs and missionaries. All these conditions, after 1967 gave rise to the Naxalite movement, which grew and spread over the coming decades.