From 2009 to 2016, an international consortium led by DESY developed the European X-ray free-electron laser European XFEL. The international research facility, which involves 12 European shareholder countries, is operated by the non-profit company European XFEL GmbH. The core of the facility is a 1.7 km superconducting linear accelerator. With an electron energy of 17.5 GeV, it is the most powerful superconducting linear accelerator in the world to date. DESY operates the accelerator on behalf of European XFEL GmbH.