Reassessing the Seamless Pagodas of Tiantong Monastery, Ningbo: Institutional History, Sino-Japanese Transmission, and Heritage Implications

The seamless pagoda (無縫塔/无缝塔) is a form of Buddhist funerary pagoda that took shape within the Chan (Zen) monastic communities of the Song dynasty. With the maturation of the Five Mountains and Ten Monasteries system, the seamless pagoda was transmitted eastward to Japan through Sino-Japanese Buddhist exchange, becoming one of the architectural-cultural carriers that crossed maritime East Asia. Existing scholarship has largely concentrated on formal/typological verification and historical contextualization, while systematic accounts of its institutional value from a cross-cultural heritage conservation perspective remain rare. Taking the Southern Song seamless pagoda at Tiantong Temple in Ningbo as its object of study, this paper a historical study of the institutional background of the seamless pagoda and of its transmission to Japan; it reassesses its significance through the analytical lens of “institutional heritage” (制度遗产), which is used here as an interpretive lens rather than as a new category of heritage. As an extended discussion, it identifies three interrelated problems in current conservation practice. Drawing on the conservation and adaptive-use experience of Japanese sites such as Sennyu-ji and Kiyomizu-dera, it proposes, as a direction for future work, an integrated conservation pathway built around four dimensions—dedicated digital documentation, the delineation of an institutional heritage zone, the establishment of a long-term maintenance mechanism, and the creation of an international dialogue platform—offering new perspectives for value excavation and conservation practice concerning tangible Buddhist cross-cultural heritage.