Why do people go to Gayā or Kāśī for piṇḍa-dāna?

tradition holds that offerings at these tīrthas give the ancestors lasting peace; it is an act of gratitude, not an obligation born of fear.

Gayā in Bihar is the foremost place in India for piṇḍa-dāna. Families offer piṇḍas on the banks of the Phalgu river, at the Viṣṇupad temple and at the sacred Akṣayavaṭa tree. Tradition holds that a śrāddha done at Gayā brings the ancestors lasting satisfaction, and many people go once in their lifetime for all their forebears.

Kāśī (Vārāṇasī) is where tradition says Śiva himself gives the liberating word to those who die there, and its ghāṭs are used for rites for the departed. Prayāgrāj and Haridvār are the most common places for immersing the ashes (asthi-visarjana), and Badrīnāth's Brahma Kapāl is also famous for śrāddha.

None of these journeys is compulsory, and nothing bad befalls a family that cannot go. A sincere śrāddha at home is complete. Going to Gayā is a beautiful way to say “thank you” to the whole line of those who came before.

Tradition says the asura Gayāsura was so devout that Viṣṇu granted that his body would become a holy land. The gods performed a great yajña on his body, and Viṣṇu steadied it with his foot, leaving the footprint now worshipped at the Viṣṇupad temple. Gayāsura asked that anyone offering piṇḍas there should bring peace to their ancestors.

Source: Vāyu Purāṇa (Gayā Māhātmya); Garuḍa Purāṇa · Gayā, Bihar — Viṣṇupad temple

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