​Las Loras UNESCO Global Geopark (UGGp) is located in the contact between the southernmost sector of the Basque-Cantabrian Basin and the North of the Cenozoic Duero basin. The bedrock is mainly made up of carbonate aquifers, mainly limestones, dolomites, and marls. Hydrogeologically, these aquifers are shared by the Ebro basin (Páramo de Sedano y Lora groundwater body, ES091MSBT002) and the Duero basin (Quintanilla-Peñahorada-Las Loras groundwater body, ES020MSBT00400004), being of the order of 80% of the UGGp drained towards the latter. This work aims to present a state-of-the-art overview of the regional hydrogeological knowledge and identifies the main lines of work for a detailed hydrogeological characterization of the Las Loras UGGp. ​