Which river is the longest flowing river entirely within the geographical boundaries of Kerala?

💡 Solution & Explanation

The Periyar River flows entirely within the state of Kerala for roughly 244 kilometers, earning the title of the lifeline of the state due to its economic and ecological significance. Other rivers like Bharathappuzha are also major regional water bodies but fall short of this length within the state boundaries. The famous Mullaperiyar Dam is constructed across this river.