The increasing availability of crowdsourced indoor geographic and semantic data presents both significant opportunities and notable challenges for the documentation and enhancement of built heritage. This work investigates the integration of OpenStreetMap (OSM) and Wikidata as complementary platforms for indoor mapping and semantic enrichment, particularly within the context of cultural heritage. OSM’s collaborative framework, supported by indoor tagging schemas, enables the detailed mapping of interior building elements, points of interest, and artworks, while Wikidata contributes structured, linked semantic information that enhances data interoperability and accessibility. Despite the growing adoption of these platforms, challenges persist in modelling complex indoor environments, achieving data completeness and facilitating user-friendly semantic integration. The proposed methodology demonstrates a flexible workflow for creating interactive 3D virtual tours of cultural buildings, leveraging OSM for spatial data and Wikidata for semantic enrichment. This approach not only supports research and educational applications but also fosters citizen science participation and interoperability with digital tools such as augmented and virtual reality. The findings highlight the transformative potential of open, crowdsourced data in advancing the discoverability, usability, and preservation of cultural heritage, while also identifying areas where further tool development and community engagement are needed to address current limitations.