Which Indian territory was popularly known as Black Water (Kala Pani) before Independence due to its notorious colonial penal settlement?

Introduction / Context:
During the British colonial period, certain remote locations were used as penal settlements where political prisoners and convicts were transported. One such place became infamous under the name Kala Pani or Black Water. It holds an important place in the history of the freedom struggle, and questions about this territory appear in both history and general knowledge sections of competitive exams.

Given Data / Assumptions:

• The question asks which Indian territory was known as Black Water.
• Options: Lakshadweep Group, Andaman and Nicobar Islands, Diu, and Aliabet and Khadiabet.
• We assume familiarity with colonial era penal settlements.
• The nickname Kala Pani refers to a place separated by sea from mainland India.

Concept / Approach:
Kala Pani was the popular name for the British penal colony in the Andaman Islands, especially the Cellular Jail at Port Blair. Prisoners sent there were effectively cut off from the mainland, and crossing the sea was symbolically associated with exile. The Andaman and Nicobar group lies far out in the Bay of Bengal and fits this description. The other options are smaller coastal or island territories without the same historical association.

Step-by-Step Solution:
Step 1: Recall that many freedom fighters were transported to a remote island prison called Cellular Jail. Step 2: This jail is located in Port Blair, which is in the Andaman Islands. Step 3: The journey across the sea and the harsh prison conditions led to the territory being referred to as Kala Pani or Black Water. Step 4: Lakshadweep is another island group, but it was not the main penal settlement associated with this term. Step 5: Diu and the small islands of Aliabet and Khadiabet also did not serve as famous colonial penal colonies in the same way. Step 6: Therefore, the correct answer is Andaman and Nicobar Islands.

Verification / Alternative check:
History textbooks and museums often mention the Cellular Jail in the Andaman Islands as Kala Pani, highlighting its role in the incarceration of Indian freedom fighters. Tourist descriptions of the Andaman and Nicobar Islands also refer to this dark chapter, while there is no such consistent association with Lakshadweep or the other listed territories. This confirms that Andaman and Nicobar Islands are the territory once known as Black Water.

Why Other Options Are Wrong:
Lakshadweep is a small archipelago in the Arabian Sea, important for its lagoons and marine life but not historically notorious as Kala Pani. Diu is a coastal enclave that was part of Portuguese India, and though it has fortifications, it is not the famous British era penal colony. Aliabet and Khadiabet are lesser known island areas and do not figure in major accounts of colonial imprisonment. Hence, these options do not match the historical reference in the question.

Common Pitfalls:
Some learners mix up Lakshadweep and Andaman because both are island groups, and on simplified maps they can appear similar. Another error is to focus only on the term Black Water and think of any water body separated from the mainland. To avoid such mistakes, firmly associate Kala Pani with the Cellular Jail at Port Blair and, therefore, with the Andaman and Nicobar Islands as a whole.

Final Answer:
The Indian territory that was popularly known as Black Water or Kala Pani before Independence is the Andaman and Nicobar Islands.