The progressive deepening of mining activities and the global pursuit of low-carbon energy systems have converged to position mines not only as sites of resource extraction but also as complex subsurface energy systems. In recent decades, increasing attention has been directed toward understanding geothermal energy extraction from mines, the coupled thermal–hydraulic–mechanical behavior of fractured rock masses, and the integration of heat management with mine safety and sustainability. This study develops a comprehensive, publication-ready synthesis and original analytical framework grounded strictly in recent and foundational literature on mine geothermal systems, underground heat transfer, backfill-based thermal storage, enhanced geothermal systems, fracture evolution, and in situ subsurface investigation technologies. Drawing on numerical modeling studies, case-based analyses, and theoretical advancements reported across mining science, geothermal engineering, and deep Earth exploration research, the article systematically elaborates on life-cycle thermal responses of mine geothermal systems, the role of groundwater flow, fracture evolution, non-Darcy flow effects, and the synergetic design of geothermal wells and backfill heat exchangers. Special emphasis is placed on how geological controls, mining-induced structural evolution, and engineered interventions such as phase-change heat storage backfill and multi-branch geothermal wells collectively influence energy extraction efficiency and thermal hazard mitigation. The methodological approach integrates conceptual modeling, numerical simulation paradigms, and interpretative analysis of reported case studies, avoiding mathematical formalism while offering deep theoretical interpretation. Results are discussed in terms of emergent patterns across different geological and operational contexts, highlighting how heat transfer pathways evolve dynamically with mining progression and backfill deployment. The discussion critically evaluates limitations in current modeling assumptions, scale effects, and uncertainties related to fracture characterization, while also connecting mine geothermal research with broader developments in deep Earth coring, gas hydrate exploration, and subsurface energy storage. By synthesizing these domains, the article advances a holistic perspective on mines as engineered geothermal systems embedded within complex geological environments. The findings contribute to both academic understanding and practical design strategies for sustainable energy recovery, mine safety enhancement, and the long-term utilization of deep subsurface space.