Previous studies have shown that people feel happier in more natural environments than in predominantly built-up environments; however, it is less clear whether the type of natural environment matters. In a large-scale experience sampling study in the Netherlands, we explored whether happiness differs by the type of natural environment experienced. We also investigated to what extent scenic beauty, peacefulness or fascinatingness are associated with momentary happiness. Smartphone apps were developed for both iOS and Android smartphones, and made freely available in both app stores. The app, named HappyHier, sent requests to fill in a short questionnaire, starting with how happy the participant feels. The requests were programmed to oversample experiences in natural environments. Location data were provided by the GPS of the smartphone, and the type of environment was determined based on a land-use map incorporated in the app. HappyHier was launched with a media campaign starting on 1st May 2016. In the following few months, over 4000 people participated, generating over 100,000 experience samples. Multi-level analyses were conducted, controlling for, among other things, being inside or outside, type of activity, type of company and weather conditions. The participants generally felt happier in natural environments, especially at the coast and in areas with low-lying natural vegetation, such as heathlands. Whether the environment is thought to be peaceful and fascinating appears to be more important for happiness than its scenic beauty. The representativeness of the data gathered by this relatively new method was explored from several angles: people, time and location