This study provides a comprehensive characterization of various hydrothermal sys-tems in Southern Peru ranging from the faulted Precordillera’s steep topography up tothe volcanic High Cordillera (>4000 m asl). The objective is to investigate thermal anoma-lies that may potentially serve as new geothermal resources.Our integrated approach com-bines: i) geochemistry from 14 hot springs sampled throughout the Tacna region, andii) 3D numerical modeling of coupled groundwater and heat transfer considering topog-raphy and faults embedded in homogeneous permeability. Water and gas analysis indi-cates that the springs located near volcanoes discharge Na-K-Cl waters with high tem-peratures (>87°C), high Total Dissolved Solid concentrations (TDS >3452 mg/L), andfree gases dominated by CO2 (>90 vol%). Springs located along the regional faults inthe Precordillera discharge Ca-SO4 and Na-K-Cl waters with moderate temperatures (27-53°C), intermediate TDS concentrations (464-2458 mg/L), radiocarbon ages between 1.4and 7.9 kyr, and free gases dominated by N2 (>95 vol%). The Aruma springs, which arelocated at the transition between the High and the Precordillera, display intermediatecharacteristics. Numerical models accurately replicate the locations and temperaturesof the fault-related springs only for permeable faults (>10−14 m2), revealing the creationof 100-km long thermal plumes along faults, locally rising up the 150°C-isotherm to about∼ 1000 m below the surface. This approach clearly distinguishes the spring origins, whichare volcanic in High Cordillera and tectonic in Precordillera. Moreover, we highlight thatsteep topographic gradient and permeable reverse faults in the Andean forearc may gen-erate considerable thermal anomalies, opening perspectives for the geothermal exploration.