The Fenix infrastructure, a collaboration among leading European supercomputing centers, supports groundbreaking advances in neuroscience. It addresses the unique computational needs of brain research, offering high-performance computing, cloud, and storage resources. The Human Brain Project (HBP) developed EBRAINS within Fenix, facilitating data collection, processing, and analysis. Notable achievements include the analysis of structural connectomes in 1000 individuals, GPU-based simulations outperforming CPU counterparts, modeling cerebellar neurons and networks, an energy-efficient neuromorphic learning algorithm, and support for The Virtual Brain. Fenix also aided the creation of a Bayesian brain network model for epilepsy diagnosis, a 3D hippocampus model, and provided access to supercomputing resources for neuroscientists, expanding their research capabilities.