Demolished by Xynthia in 2010, the welcome pavilion of the Museum Clemenceau in in Saint-Vincent-sur-Jard has been rebuilt to acquire visitors and reinstate the National Monument. One of the main site’s premises is to create within the massing of the old structure composed of two juxtaposed volumes. Our proposal for the new entrance pavilion is a discrete rectangular volume, gently embedded into its surroundings. Respecting the site’s heritage, the new addition is acting as a gateway to the gardens. We imagined the structure as a concrete monolithic volume emerging from the ground. Its hull, entirely built of concrete, blurs with the beach, the dunes, and the courtyard, while clearly defining a passage from the open public space to the intimate gardens of Clemenceau. Working with the site constraints, the new project revolves around a central nave - a pavilion acting as a ‘‘transition structure’’, accommodating reception, museum shop and educational space, and simultaneously connecting two additional volumes for technical facilities and the personnel. The welcome pavilion is constructed in two different ways according to the volumes. The outer body is entirely made of smooth sand-coloured concrete, while the interior, also of concrete, is robust. The constraint of rebuilding in the exact massing of the old building and following law restrictions after the storm Xynthia is turned into a program’s advantage to provide optimized space, allowing simple visitor flow. The pavilion, with its sloped concrete roof, with the different implemented techniques of using concrete, and the challenges of constructing on-site under Monuments Protection lead to new potentials and discovery, expressing the sensitive aspect of concrete and its visionary implications.