<p>A prominent example of cultural diplomacy is the intentional use of the shared Buddhist heritage of India and the Association of Southeast Asian Nations (ASEAN) to fortify diplomatic relations. The notion that “holy geographies” can serve as diplomatic pathways is examined in this study. It looks at how popular Buddhist pilgrimage routes, especially those that connect Bodh Gaya, India, to Bagan, Myanmar, and beyond, are being utilised to advance regional integration, political civility, and economic cooperation. These days, religion and culture are effective tools for regional cooperation in the age of soft power and multipolar diplomacy. Through a number of case studies, such as India-Myanmar (Bagan), India-Thailand (Bodh Gaya corridor), and India-Vietnam (Nalanda–Dong Thap engagement), this paper explores the intersection of religion, diplomacy, and geopolitics, drawing on international relations theory, cultural diplomacy, and postcolonial studies. The key objectives of this paper&#xa0;are to assess models of collaboration between India and ASEAN, comprehend the function of pilgrimage circuits in cultural diplomacy, and examine the policy and infrastructure results of Buddhist diplomacy. Drawing on constructivist theory and qualitative analysis of policy documents, pilgrimage flows, and institutional cooperation mechanisms, this study demonstrates that Buddhist pilgrimage circuits operate as sites of identity construction, diplomatic trust-building, and soft power projection in India–ASEAN relations. It investigates a range of MoU’s, tourist partnerships, and international agreements in order to comprehend the ways in which Buddhism is employed as a soft power tool. This essay comes to the conclusion that incorporating religious history into contemporary diplomacy opens up new avenues for Asian regionalism and establishes India as a key player in the changing cultural and geopolitical environment of ASEAN.</p>