- This archipelago is composed of 265 big and small islands (203 Andaman islands + 62 Nicobar Islands).
- The Andaman Islands are divided into three main islands, i.e. North, Middle and South.
- Duncan passage separates Little Andaman from South Andaman.
- The Great Andaman group of islands in the north is separated by the Ten Degree Channel from the Nicobar group in the south.
- Port Blair, the capital of Andaman Nicobar Islands, lies in the South Andaman.
- Among the Nicobar Islands, the Great Nicobar is the largest. It is the southernmost island and is very close to Sumatra island of Indonesia.
- The Car Nicobar is the northernmost island.
- The Barren Island (the only active volcano in India) and Narcondam Islands (an extinct or dormant volcano), north of Port Blair, are volcanic islands.
- Saddle peak (737 m) in North Andaman is the highest peak.