We examined the effects of a two-week nature-based well-being intervention. Undergraduates (N = 395) were randomly assigned to one of three conditions: nature, human-built or a business-as-usual control. Participants paid attention to how nature (or human-built objects, depending on assignment) in their everyday surroundings made them feel, photographed the objects/scenes that evoked emotion in them and provided a description of emotions evoked. Post-intervention levels of net positive affect, elevating experiences, a general sense of connectedness (to other people, to nature and to life as a whole) and prosocial orientation were significantly higher in the nature group compared to the human-built and control groups. Trait levels of nature connectedness and engagement with beauty did not moderate nature’s beneficial impact on well-being. Qualitative findings revealed significant differences in the emotional themes evoked by nature vs. human-built objects/scenes. This research provides important em...