The purpose of this study is to evaluate to which extent the rail transport mode can improve the environmental situation in Europe if it were to be at the centre of sustainability-driven policies. In particular, it aims at estimating a relative picture of the CO2 emissions generated by short-distance air passenger transportation in Europe, which could have been transferred to high-speed rail and produce less CO2. This study follows a three-step methodology. Firstly, it calculates the number of passengers travelling on each route between cities and estimates the total CO2 emissions. Subsequently, it leverages the current literature on CO2 consumption from railway passenger transport. Lastly, it estimates the possible scenarios in terms of CO2 emissions that would have followed adequate sustainability-driven policies. The study found that short-range aviation in EU28 produced 9.2 million tons of CO2 in 2017, which represents about 5% of total aviation emission, about 1% of total transport emission and about 0.2% of total CO2emission. Furthermore, the CO2 production on the 175 routes analysed increased until 2019, while precise policies could have allowed saving 582 MT CO2. The effects of the COVID-19 outbreak on the European transport sector increases the relevance of this study. To avert the “return to normality” vis a vis Greenhouse Gases (hereinafter “GHG”) emissions from the sector, it will be necessary to introduce structural changes. As Austrian Airlines or KLM bailouts show, environmental concerns might finally influence the decision-making process on public transportation. In the context of a green recovery, this study not only lays the foundation for further contributions addressing the CO2 production from EU-wide sectors but also underlines the role the railway can play in environmentally friendly transportation.