Understanding the size and spatial distribution of material stocks is crucial for sustainable resource 22 management and climate change mitigation. This study presents high-resolution maps of buildings and 23 mobility infrastructure stocks for the United Kingdom (UK) and the Republic of Ireland (IRL) at 10 24 meters, combining satellite-based Earth observations, OpenStreetMaps, and material intensities 25 research. Stocks in the UK and IRL amount to 19.8 Gigatons or 279 tons/cap, predominantly aggregate, 26 concrete and bricks, as well as various metals and timber. Building stocks per capita are surprisingly 27 similar across medium to high population density, with only the lowest population densities having 28 substantially larger per capita stocks. Infrastructure stocks per capita decrease with higher population 29 density. Interestingly, for a given building stock within an area, infrastructure stocks are substantially 30 larger in IRL than in the UK. These maps can provide useful insights for sustainable urban planning and 31 advancing a circular economy.