The Grand'Place in Lille, a prominent public square today, has a rich and complex history that is being explored through the INSULA research project. This initiative aims to digitally reconstruct how the square looked and sounded on June 12, 1448, using historical records to create a multisensory experience. Despite the fact that almost no physical remains from the medieval period are visible today, the project uses digital modeling to test historical theories and share them with the public, acting as both a research and educational tool. The first known reference to the market square, which corresponds to parts of today's Grand'Place and Place du Théâtre in Lille, dates back to 1127. However, the square's character changed significantly in 1651 when the construction of a commercial exchange building split the space into two. This square was not only a center for commerce but also for political and social activities, hosting events such as tournaments, festivals, and religious processions. Today, very little of the medieval square remains. A careful observer might notice a few hundred granite cobblestones embedded in the ground of the Grand'Place. These were discovered during an archaeological excavation in 1989 and are the only visible remnants of the medieval era on the current squares. Launched in 2023, the INSULA project focuses on creating a digital reconstruction of the square as it was on June 12, 1448. This reconstruction includes both visual and auditory elements, offering a glimpse into what an ordinary day in the city's history might have been like. The project is based on archival records, and all choices made in the reconstruction are justified by historical sources or relevant comparisons. Recreating the soundscape of the medieval square is particularly challenging, as sound rarely leaves physical traces. However, historical documents such as deliberation records, city accounts, and police regulations provide clues about the sounds present in the square. These include the ringing of bells from religious buildings, public criers announcing news, the noise from workshops, livestock on market days, and the echoes of traffic on granite paving. The INSULA project uses these clues to create a detailed sound map of the square. Additionally, the project seeks to make this reconstructed history accessible to the public through digital tools and immersive experiences, helping to bridge the gap between academic research and public understanding.