'India and Adjacent Countries (IAC)' is a regional and arbitrary system for India and adjoining countries (largely those under British control/influence or of interest, during pre-independent India).
Topographical maps under this series was prepared by the Survey of India till the coming into existence of Delhi Survey Conference in 1937. Henceforth, the preparation of maps for the adjoining countries was abandoned and the Survey of India confined itself to preparing and publishing the topographical maps of India as per the specifications laid down for the International Map of the World Series. A map numbering system was developed to give each map a unique number.
The map series is based on Polyconic projection on Indian Geodetic Datum.
Map numbering is of the form '12A/1':
India and Adjacent Countries map numbers are especially used by Survey of India maps, especially those printed before adoption of the Open Series Map/Defence Series Map.
To view the distribution in Google Earth download this KMZ.
Lookup India and Adjacent Countries map numbers in Map Number Lookup.▲