The Aravalli Mountain System (AMS) is one of the oldest fold orogens in the world, serving as a natural boundary against desertification in north-western India. The AMS has high environmental importance and faces accelerated soil degradation driven by both anthropogenic pressures and climatic shifts. Still, high-resolution measurements of soil erosion processes have not been conducted on the AMS scale. The present study assesses long-term LULC transitions between 2001 and 2021, identifies high-resolution short-term LULC dynamics between 2017 and 2024, and models spatiotemporal soil erosion dynamics using the RUSLE model. The findings indicate that LULC has changed rapidly, with built-up areas increasing by 53 per cent at the expense of rangelands and croplands. These drivers resulted in a 13.8 per cent increase in the mean annual soil loss between 2017 and 2024, from 1.59 to 1.81 t/ha/yr, while forest cover has increased over the timescale, as is evident in this study. The steep slopes, susceptible soils, and mining areas are strongly associated with erosion hotspots. Increased soil erosion in the AMS despite a significant increase in afforestation highlights that local conservation cannot compensate for massive land conversion. The present study provides a scalable, high-resolution framework for assessing soil erosion in vulnerable old mountain systems globally for sustainable land-use planning, mineral governance, and integrated conservation to protect for future generations.