Does the Rigveda mention specific sacred places for Pind Daan?

The Rigveda establishes the general theological framework for ancestral offerings at sacred rivers and fire altars, but the specific designation of tirthas like Gaya, Prayagraj, and Varanasi as supreme locations for Pind Daan comes primarily from the Puranas — particularly the Vayu Purana (on Gaya), the Matsya Purana (on Prayagraj), and the Kashi Khanda of the Skanda Purana (on Varanasi). The Manusmriti (3.203) is the Smriti text that most explicitly lists the tirthas where Pind Daan has multiplied spiritual effect.