The article is devoted to the analysis of the legal category “source of increased danger”. The authors consider the discussion between approaches that treat this source as an activity or as a material object. The uncertainty of legislative regulation and the breadth of judicial interpretation of the concept are noted. The paper emphasizes that it is almost impossible to create an exhaustive list of sources of increased danger. Based on the analysis of the norms of current legislation and judicial practice, the position in favor of the need to separate the concepts of “a source of increased danger” and “activities that pose a danger” is substantiated. The authors conclude that the activity is dangerous, and the term “source of increased danger” plays an “official” role to specify the person responsible for possible harm.