While there is considerable evidence that therapeutic landscapes have a positive impact on wellbeing, we know little about the mechanisms through which this impact occurs. In this paper we go some way toward addressing this gap. Drawing on in-depth interviews with 12 people aged between 52 and 75 years of age, who are engaged in nature-adventure activity in the UK, we focus on what they understand by ‘wilderness’; their experiences of nature-adventure in wilderness settings; and the impact of these experiences on their wellbeing. Moving beyond the largely behavioural focus of laboratory-based studies prevalent within environmental psychology, we highlight the importance of understanding the role of the contextual in the therapeutic relationship. That is, how relational, embodied, social, lifecourse and/or cultural factors that are constitutive of wilderness environments impact wellbeing for those engaged in nature-adventure activity in later life. In doing so, we map out a working model of the mechanisms that impact wellbeing within this context. Our data suggest that there is no one single mechanism, rather we need to think about a range of mechanisms, often operating across a series of spectra (active/passive; safety/risk; alone/socially etc) and importantly, each are connected to place. Hence, we suggest, that where that activity takes place is instrumental for wellbeing.