“Gaudí Code, The Untold Experience” invites visitors to see Gaudí’s work from the inside, rather than simply looking at his buildings. The experience combines interactive spaces, projections, mixed reality and virtual reality to explore the geometry, light and structures that shaped his way of working and link his work as a whole. The most unexpected part comes at the end. Thanks to years of research by the Càtedra Gaudí at the Universitat Politècnica de Catalunya (UPC), visitors can explore projects that were never built, such as the Hotel Attraction in New York and the Monumental Fountain planned for Plaça de Catalunya. It is a rare opportunity to move from the Gaudí we know to the Gaudí who existed only on paper.