The Finnish–Russian borderland has transformed in the last three decades from two isolated national territories into a transition zone, where the ‘other’ culture and society is ever more present. This paper analyses what kinds of perceptions Finnish and Russian children have of the border and the borderland today. It also examines children’s territorial identifications in the borderland. The research is based on 263 mental maps collected from 9–15-year-old children in the cities of Lappeenranta (Finland) and Vyborg (Russia) and the village of Pervomayskoe (Russia) between 2013 and 2017. The analysis of the maps illustrates that the children participating in the study perceive the Finnish–Russian border mainly as a place for border crossings, although they continue to use the border as a tool for constructing socio-spatial distinctions. In this way, the children actively participate in processes of bordering and play an important part in the social life of the borderland. The participants’ perceptions of the borderland are connected to the national and local contexts that they live in but vary widely between individuals. The paper argues that the local border-related phenomena and children’s border-crossing experiences are increasingly relevant for their national and local identification processes. Besides providing novel information regarding Finnish and Russian children’s perceptions and identifications in the Finnish–Russian borderland, the paper adjusts the mental mapping method to a borderland context and enhances our understanding of the complexity of the bordering processes taking place in borderlands.