The materiality of ritual performance is a growing focus for archaeologists. In Europe, collective ritual performance is expected to be highly structured and to leave behind a loud archaeological signature. In Australia and Papua New Guinea, ritual is highly structured; however, material signatures for performance are not always apparent, with ritual frequently bound up in the surrounding natural and cultural landscape. One way of assessing long-term ritual in this context is by using archaeology to historicize ethno-historical and ethnographic accounts. Examples of this in the Torres Strait region, islands between Papua New Guinea and mainland Australia, suggest that ritual activities were materially inscribed at kod sites (ceremonial men's meeting places) through distribution of clan fireplaces, mounds of stone/bone and shell. This paper examines the structure of Torres Strait ritual for a site ethnographically reputed to be the ancestral kod of the Mabuyag Islanders. Intra-site partitioning of ritual performance is interpreted using ethnography, rock art and the divergent distribution of surface and sub-surface materials (including microscopic analysis of dugong bone and lithic material) across the site. Finally, it discusses the materiality of ritual at a boundary zone between mainland Australia and Papua New Guinea and the extent to which archaeology provides evidence for Islander negotiation through ceremony of external incursions.