The southern-most tip of the Indian mainland is Kanniyakumari.

Explanation:
Kanniyakumari, also known as Cape Comorin, is located at the southernmost tip of the Indian mainland. It is a town in the state of Tamil Nadu and is situated at the confluence of the Arabian Sea, the Bay of Bengal, and the Indian Ocean. Here are some key points about Kanniyakumari:

1. Location: Kanniyakumari is situated in the Kanyakumari district of Tamil Nadu. It is located at approximately 8 degrees 4 minutes north latitude and 77 degrees 34 minutes east longitude.

2. Geographical Significance: The town of Kanniyakumari is known for its geographical significance as it is the point where the three major bodies of water - the Arabian Sea, the Bay of Bengal, and the Indian Ocean - meet. This unique location makes it a popular tourist destination.

3. Vivekananda Rock Memorial: One of the major attractions in Kanniyakumari is the Vivekananda Rock Memorial, which is situated on a rocky island about 500 meters offshore. It is dedicated to Swami Vivekananda, a renowned spiritual leader, and offers panoramic views of the surrounding sea.

4. Thiruvalluvar Statue: Another prominent landmark in Kanniyakumari is the Thiruvalluvar Statue, which is a 133-feet tall stone sculpture of the Tamil poet and philosopher Thiruvalluvar. It stands on a small island near the shoreline and represents the rich cultural heritage of Tamil Nadu.

5. Sunrise and Sunset: Kanniyakumari is known for its breathtaking views of both sunrise and sunset. Owing to its location at the southernmost tip of the Indian mainland, visitors can witness the sun rising and setting over the ocean, creating stunning visual spectacles.

In conclusion, Kanniyakumari forms the southern-most tip of the Indian mainland and is a place of great geographical and cultural significance. It attracts tourists from all over the world who come to witness the convergence of the seas and experience the beauty of the sunrise and sunset.