NEURONAV is a PNT solution designed to enhance the precision and reliability of GNSS receivers in maritime transport. Leveraging deep environmental knowledge, it mitigates multipath effects through Machine Learning (ML), correlating multipath error with vessel geometry. Key features include automatic ML multipath model training and validation, estimation of 2D/3D-position error vector, and reference ship layouts for expedited model training. NEURONAV also evolves and trains during its lifetime, accommodating for ship layout changes. It's an augmentation of the GNSS receiver, specifically tailored for ships in transit or operating in ports.