<![CDATA[Nunukan Regency occupies a strategically important Indonesia–Malaysia borderland where Indigenous and migrant communities maintain diverse ecological knowledge, customary institutions, social values, place-based products, and cross-border livelihood practices. These resources are relevant not only to cultural preservation but also to the development of community-governed cultural tourism; however, the evidence base remains fragmented across disciplines and locations. This review maps the forms and distribution of local wisdom documented in Nunukan, examines how cross-border interaction shapes cultural continuity and social resilience, and identifies preservation challenges, research gaps, and implications for sustainable cultural tourism. A PRISMA-2020-informed evidence-mapping review was conducted using 22 Indonesian- and English-language search strings on 20 September 2026, supplemented by backward citation searching. Of 205 records identified, 10 documents published between 2012 and 2026 met the eligibility criteria and were synthesised thematically. Six studies focused on Krayan, three on Sebatik, and one on Lumbis. The most consistently documented domains were medicinal-plant knowledge, Lundayeh customary institutions, Tidung cultural values, mountain-salt production, and cross-border economic relations. Cross-border ties supported markets, kinship, and everyday resilience, yet also reproduced dependence, inequality, and youth out-migration. Preservation pressures included weakening intergenerational transmission, biological-resource vulnerability, and limited institutional support. The review therefore identifies rich cultural assets but an uneven and methodologically narrow evidence base. For tourism-oriented development, these findings support community authority, benefit sharing, cultural protocols, and heritage interpretation that treats local wisdom as living heritage rather than as a decontextualised commodity.]]>
