Which is the longest river of peninsular India?

Introduction / Context:
This question focuses on Indian physical geography, specifically the major rivers of the peninsular region. Knowing which rivers are longest, where they flow, and where they drain is fundamental for exam questions in geography and general studies. The peninsular rivers originate mostly in the Western Ghats or central highlands and flow eastward into the Bay of Bengal or westward into the Arabian Sea.

Given Data / Assumptions:

• The question asks for the longest river in peninsular India.
• Options are Narmada, Godavari, Mahanadi, and Cauvery.
• We consider only rivers whose basins mainly lie in the peninsular region, not the Himalayan system.
• No detailed calculation of river length is required; it is a fact-based recall question.

Concept / Approach:
Among the major peninsular rivers, the Godavari is the longest. It is often referred to as the "Dakshin Ganga" or "Ganga of the South." The river originates in the Western Ghats in Maharashtra and flows through several states before emptying into the Bay of Bengal. While Narmada, Mahanadi, and Cauvery are also important peninsular rivers, their lengths are shorter than that of the Godavari.

Step-by-Step Solution:
Step 1: List the major peninsular rivers: Godavari, Krishna, Cauvery, Narmada, and Mahanadi, among others. Step 2: Recall that the Godavari is the longest of these, with a length of about 1465 kilometres, making it the longest river in peninsular India. Step 3: Compare with the approximate lengths of the other options. Narmada, Cauvery, and Mahanadi are all shorter. Step 4: Therefore, choose Godavari as the correct option.
Verification / Alternative check:
Standard geography textbooks and maps often mark the Godavari as the longest river in peninsular India and the second-longest river in India after the Ganga. This fact is usually highlighted in exam-focused notes. Remembering the nickname "Dakshin Ganga" also helps verify that Godavari is the river being referred to.

Why Other Options Are Wrong:

• Narmada: A major west-flowing river, but shorter than the Godavari.
• Mahanadi: Important for Odisha and Chhattisgarh, but again shorter than the Godavari.
• Cauvery: A significant river for Karnataka and Tamil Nadu, but not the longest in the peninsular region.

Common Pitfalls:
Some students mix up "largest river basin" and "longest river" or confuse the role of Krishna with that of Godavari. Others may recall that Narmada is prominent because it flows westward and cut a rift valley, but prominence does not equal length. Focusing on the specific measure asked in the question, which is length, helps avoid such confusion.

Final Answer:
The longest river of peninsular India is the Godavari.