The issue of inequality in the use of urban transport space is particularly important in today’s car-saturated cities. Increasing the convenience, safety and respect for the rights of vulnerable road users, including in particular pedestrians and cyclists, is emerging as a particular challenge. Grassroots initiatives of city residents, who become cycling advocates and cycling activists, are confronting this problem. Among various forms of activism there is also the organisation of ‘critical masses’, which were originally intended to remind us about the rights of this group of road users through a simultaneous passage of multiple cyclists through the streets of the city. From the late 20th century to the present day, such events have undergone change. The aim of this study was to investigate how today’s critical masses differ from their 1990s prototypes. The research analysed bike critical masses organised in Poland, a country with an underdeveloped cycling culture and low cycling modal share. At one such event, a survey was also conducted to determine why participants chose to attend. The study confirmed that contemporary bicycle critical masses are recreational events promoting cycling.