With the increasing density of built spaces in urban areas, the need for open spaces increases every day. Squares are one of the most important of these open spaces. Urban squares allow various activities and exhibit functional differences based on location and culture. The diversity of activities conducted in squares is extremely important for the quality and viability of liveable urban spaces. Urban residents prefer spaces that are suitable for individual requirements and desires and allow for a variety of activities. These spaces also contribute to social life. This article aimed to determine the user profile, occupancy, facilities and activity diversity at the Ataturk Plaza (Trabzon urban square) in Trabzon, the capital city of Trabzon Province, Turkey. The occupants of the square and their numbers were analysed via the behaviour observation method. As a result of the observations conducted in the square over one year, 17 activities were identified. The majority of these activities were necessary activities and that the most common activity was walking. The occupancy density and distribution in the square were analysed using the Geographical Information System (GIS). These research findings and analyses could serve as a guide for future urban square and urban open space designs.