The existing Critical Infrastructure (CI) of Europe in the water, energy, urban and transport sector is facing major challenges because of pressures such as climate change, extreme weather, geo-hazards, aging and increased usage in combination with pivotal changes in the CI to meet long-term societal goals (e.g. energy transition).<br/><br/>The GEOLAB research infrastructure consists of 11 unique installations in Europe aimed to study subsurface behavior and the interaction with structural CI elements (e.g. a bridge) and the environment. The installations already represent the best of the state-of-the-art available today. However, up to now, work in these installations has been independent and uncoordinated, significantly limiting the outcome for users among academia, industry and CI network managers. There is a gap in the European research landscape for an integrated, advanced research infrastructure in this field. This GEOLAB initiative will fill that gap.<br/><br/>The scientific research community will use the innovative capabilities of GEOLAB from the JRAs to perform ground-breaking research, to be published in international peer reviewed, high impact journals. For CI managers and policy makers, the activities will result in a more comprehensive understanding of the challenges facing CI and evidence to base decision making upon. The construction industry will use GEOLAB to proof innovative solutions for the CI and so gain more leadership in the industrial and enabling technologies. The GEOLAB consortium will engage in different types of innovations processes with Small and Medium-sized Enterprises (SMEs). There will be close interaction with those SMEs that develop user-friendly engineering software from numerical modelling advances which are validated in the TA projects. We will explicitly challenge SMEs on sensing, new materials and other niches for innovative solutions, which will have spinoff in other fields of application, contributing to the competitiveness of Europe.