<p>Geoheritage resources in Nigeria remain underdocumented in ways that link their scientific significance with their cultural meanings and practical tourism potential. This study presents an integrated assessment of selected geosites in Oyo State, southwestern Nigeria, to evaluate their geoheritage significance and geotourism prospects within a sustainable regional development framework. The study combines geological field mapping, drone-assisted visual documentation, GIS-based terrain analysis, community-based interviews, numerical geosite evaluation, and application of the Geosite Assessment Model (GAM). Our geological observations reveal diverse lithological and structural features, including granitic terrains, pegmatitic intrusions, and migmatitic outcrops that contribute to the scientific value of the sites. Terrain analysis further highlights strong spatial contrasts across the study area, with rugged upland landscapes in the north and gentler lowlands in the south. Community interviews show that several geosites also function as cultural landscapes rooted in local memory, spirituality, and identity. The integrated assessment shows clear differences among sites in terms of scientific value, scenic appeal, accessibility, functional attributes, and tourism readiness. Ado Awaye Hill emerged as one of the strongest multifunctional geosites, while Asejire Dam showed relatively favorable supporting amenities. In contrast, several other sites are still constrained by weak infrastructure, limited accessibility, and insufficient tourism services. Overall, our results indicate that the geosites of Oyo State have substantial geoheritage and geotourism potential, but their contribution to regional development will depend on improved conservation planning, community participation, and targeted investment in visitor infrastructure. Importantly, our study provides a transferable framework for geoheritage assessment in data-scarce regions of sub-Saharan Africa.</p>