<p>The angle of repose (AoR) is a crucial parameter that characterizes the behavior of granular materials in various applications. This study aims to investigate the influence of various intrinsic and external factors on the AoR of gravel piles. Gravel samples were collected from diverse locations within an iron ore mine and analyzed for intrinsic properties such as grain size, density, moisture content, and shape. Subsequently, the AoR of the samples was determined using the cylinder-lifting test, while external variables such as the ratio of material height to cylinder diameter, cylinder diameter, and bed roughness were varied. A total of 30 tests, programmed by the design of experiments, were conducted. A linear model was developed to correlate the AoR with influential factors using statistical analyses. The findings revealed the substantial negative impact of gravel grain size on the AoR of gravels. Additionally, they emphasized the significance of bed roughness in the AoR of gravel piles. The introduction of grooves on the gravel pile bed led to a significant average increase of 35% in the AoR. These insights underscore the potential of environmental modifications to enhance the AoR and offer practical implications for predicting the AoR of gravel piles in mining settings.</p>