The subject of my diploma thesis is a design and complex solution of the selected part of the interior of the sports and regeneration center - FIT & SPA CENTER in Dolný Kubín. The project of the thesis - proposal of the interior - directly follows the pre-diploma project prepared in the winter semester 2016/2017 within the class Atelier III.The thesis is divided into text and plan parts. Several selected plans from the pre-diploma project, which follow the plans of the solved part of the interior, are included within the text part.FIT & SPA CENTER, designed as a pre-diploma project, is located in Dolný Kubín, in the quiet zone of the town section Veľký Bysterec. The land is currently unused and neglected, but it has an enormous potential due to its convenient location close to the town center and beautiful views. Orava river in its vicinity enhances its attractivity. The project aims to revitalize this land, to raise quality of the location by its services and to benefit the surrounding area.The goal was to create an object that takes advantage of the given site, supports the potential, and by its functions it appropriately complements sport activities in the area and at the same time increases the quality of life of the inhabitants of Dolný Kubín. The center is designed for locals and people looking for an active rest and relaxation. The design represents a wellbeing building - a building for sport use complemented by a wellness area and a commercial operation. The object with its features is thematically linked to the surroundings. In close proximity there is, e.g., an ice-hockey stadium, a football stadium, a court with artificial grass, a volleyball court, an aquapark, a cross-country skiing trails.The integral part of the goal was to design a modern building that would not only fulfill its function and provide comfort, but would fit into the surrounding environment and add some aesthetic values that are currently lacking in the given locality. With its mass, the building respects the specific expression of a compact structure of the surrounding architecture of residential buildings reaching a maximum level of 6 floors. The building creates a modern landmark in the locality.During designing, it was important to unambiguously organize the individual functional units so they will not cross each other and the object operation will work smoothly. At the same time it was necessary for the functional units to be interconnected. The attempt was to achieve a clearly divided operation. This simplicity and functionality of the building is reflected in its architecture.The selected part of the interior, which is being solved in the thesis, consists of the entrance area on the ground floor - a foyer with reception and a wellness area on the second floor. The foyer is connected to a sale of sport equipment and the wellness area is connected to a coffee bar.