Highlights: The use of real-time rendering with ray tracing technology as a tool for heritage virtual reconstruction is proposed. The possibilities that the use of next-generation video game engines, specifically Unreal Engine, offer are evaluated in terms of their application in heritage virtualisation. The first results of the virtual reconstruction of the Tartessian site of Casas del Turuñuelo are presented, after using real-time ray tracing technology as a research method to create and review architectural hypotheses. Abstract: Virtual reconstruction has become a fundamental tool to study and analyse archaeological heritage, given its usefulness for both research and dissemination. Although the discipline has advanced exponentially in recent years, the workflow used in most jobs is still based on the offline methodology as the preferred rendering engine. In contrast, this paper proposes the substitution of this methodology with the new ray tracing in real-time rendering technology; specifically, the authors used Unreal Engine to develop virtual reconstruction work as a research tool during the excavation of an archaeological site, as well as to disseminate the results of the study of each phase. The aim is to exploit the advantages of the immediacy of calculating high-quality and realistic lighting and materials, as well as the interaction and immersion in the virtual model that this system for the development of video games offers. This paper highlights: a) the benefits detected when using real-time technology in heritage reconstruction during the work carried out to date, and b) its limitations and its future evolution with the development of the technology. To demonstrate the usefulness of this tool, the authors present the reconstruction project of the Casas del Turuñuelo site (Guareña, Badajoz). It is one of the best preserved protohistoric sites in the Western Mediterranean, which is why applying this technology to this case study was considered appropriate. The excellent architectural preservation of the Casas del Turuñuelo building is an extraordinary example to assess the usefulness of applying video game engines to heritage reconstruction. This settlement is one of the first known examples of this technology being applied to heritage, specifically, to the virtualisation of an archaeological site under excavation. This methodology and its improvements will be applied to the virtual reconstruction of this project as the excavation of this site advances; thus, one of the main outreach tools developed within the framework of Building Tartessos project will be made available to users as a final product.