Background: The constantly growing number of elderly and disabled people in Polish society forces decision-makers, investors, and architects to take action to eliminate obstacles in access to public buildings. Educational and cultural facilities, including libraries, are particularly important for ensuring the well-being of this particular group. These facilities should be characterized by universal accessibility, including appropriate location that facilitates integration with the environment not only geographically but also socially, the reduction of all barriers, and the implementation of solutions that enable the use of all their areas by people with special needs. The spatial solutions of these facilities should counteract social exclusion. The aim of the article is an attempt to diagnose the current state of adaptation of public libraries to the needs of elderly and disabled people in one of the representative cities in Poland. Material and Methods: The article describes the conducted survey research. The main research tool used was correlated quantitative-statistical and qualitative research methods. The undertaken activities were both theoretical (analysis of the relevant literature and sample solutions) and practical (field research, field trips). The research concludes with a comparative analysis of the correlations between specific variable parameters of the outdoor and indoor spaces within the analyzed facilities. Results: This article presents the results of research related to the accessibility of public libraries in Białystok for seniors. It was found that most libraries in the city are located in facilities that were not originally planned, designed and implemented to perform their current function. The research results indicate that in a significant number of facilities there are architectural barriers that make it difficult and often impossible to overcome them not only for people in wheelchairs, but also for people with limited mobility and other psychomotor dysfunctions. Conclusions: The analysis of the results of the conducted research confirms the accepted thesis about the insufficient adaptation of buildings in which libraries are located in the city of Białystok to the needs of senior citizens and disabled. The research results can be used in planning remedial actions and improving the quality of the architectural space of existing and planned public libraries. Med Pr Work Health Saf. 2025;76(4)