The Integrated Carbon Observation System (ICOS) is a European-wide greenhouse gas research infrastructure. ICOS produces standardised data on greenhouse gas concentrations in the atmosphere, as well as on carbon fluxes between the atmosphere, the earth and oceans. ICOS provides long term, high quality observations that follow the global standards for the best possible quality data on the atmospheric composition for greenhouse gases (GHG), greenhouse gas exchange fluxes measured by eddy covariance and CO2 partial pressure at water surfaces. ICOS data is based on the measurements from over 140 stations across 12 European countries and is available at the ICOS data portal with open access to data and metadata for download and instant graphical preview. A virtual research environment is provided as well with Jupyter Notebooks to the public, for collaborative research groups and education with direct access to the data.