A group of eleven European gas infrastructure companies from nine EU member states developed a plan for a dedicated hydrogen transport infrastructure. The plan shows that existing gas infrastructure can be modified to transport hydrogen at an affordable cost. The plan, developed by Enagás, Energinet, Fluxys Belgium, Gasunie, GRTgaz, NET4GAS, OGE, ONTRAS, Teréga, Snam and Swedegas, foresees a network gradually emerging from the mid-2020s onwards to an initial 6,800 km pipeline network by 2030, connecting ‘hydrogen valleys’. By 2040, a hydrogen network of 23,000 km is foreseen, 75% of which will consist of converted natural gas pipelines, connected by new pipeline stretches (25%). The plan shows that two parallel gas transport networks will emerge: a dedicated hydrogen and a dedicated (bio)methane network. The network can be used for large-scale hydrogen transport over longer distances in an energy-efficient way, also taking into consideration hydrogen imports. The network is estimated to cost between 27 to €64 billion, with a levelised cost between €0.09-0.17 per kg of hydrogen per 1000 km. The wide range in the estimate is due to uncertainties in (location dependent) compressor costs.