To begin with, only farms
Andaman and Nicobar Islands, Bihar, Haryana, Karnataka, Manipur, Delhi, Rajasthan, Punjab, Telangana and West Bengal lack records for parts of their land area, according to the NCAER, which obtained the information from state governments as a part of its effort to create a Land Records Services Index that measures the quality of state land records. The data on unsurveyed land relate to only unforested areas.
There are different reasons for why various regions remained surveyed, many of them going back to the time the British administered India. While initial land surveys in India date back to the Mughal Empire, the most prominent ones were carried out by the colonial government in the late 19th and early 20th century, according to a report of the department of land resources under the Ministry of Rural Development.