The new building serves as a repository for a unique library, assembled by a professor at the Zurich Polytechnic Institute (ETH Zürich). It consists of 50,000 volumes, the earliest of which date back to the 17th century. For the most part, these are sources on the history and theory of architecture and philosophy. Although the site is due to the proximity of Ekslin's own house (the two buildings are connected above the ground by a glass pavilion, and underground by several new premises for the collector's personal use), its location also carries symbolic significance. The library stands on the old pilgrimage route to the Spanish city of Santiago de Compostela, where the relics of the Apostle James are located. Therefore, both Exlin himself and Botta considered the new building as a point of intersection of the paths of the spiritual and material worlds, as well as a hub of cultural ties between Northern and Southern Europe.
It took ten years to design and build the small structure.
In the plan, the library resembles a Latin D lying on a straight crossbeam. Outside, its walls are faced with pink Veronese stone. Inside, the axis of the building is a steep staircase connecting all its levels. The lobby displays a variety of artworks from the Exlin collection; from there the visitor enters the reading room, which consists of two storeys of the book depository and is located in the center of the building.
In addition to the functions of the library, the new building will also serve as a research center: training courses on Baroque architecture, international conferences and the so-called "Einsiedeln Architecture Symposia" will be held there.
