Abstract
This article addresses the study of the internal hydraulic infrastructure of the Royal Monastery of San Lorenzo del Escorial. The vast network of pipes that supplied water to the numerous fountains, tanks, and other devices in the building. The methodology was based on two fundamental pillars: an analysis of the historical sources related to water and a cataloguing of the preserved architectonical remains of the infrastructure. A new sketch of the water supply network of the building has been drawn using ArcGIS Pro software. In doing so, this article provides a more accurate and detailed knowledge of the building's plumbing system.