| State | Description |
|---|---|
| I. Arunachal Pradesh | The capital is named after a fort, and the State has two National Parks |
| II. Nagaland | The State came into existence on the basis of a Constitutional Amendment Act |
| III. Tripura | Initially a Part 'C' State, it became a centrally administered territory with the reorganization of States in 1956 and later attained the status of a full-fledged State |