Walkability has become a major topic in mobility and transport research over the last decade. To investigate the complex nature of walkability, a combination of quantitative and qualitative methods is often suggested. This paper introduces a mixed methods approach applied in a research project examining urban walkability at the neighbourhood scale in three European cities: Gothenburg, Dortmund and Genoa. Of the four methods used, our innovative citizen-science based Walking Route Assessment is the focus of this paper. The complementary roles of other methods (spatial modelling, household survey and walk-along interviews) are also discussed to reveal the benefits of mixed methods approaches for future walkability studies. The paper identified a set of prerequisites for improving perceived walkability. To enhance walking environments, more green space and place-making aspects should be taken into account, along with improving traffic safety and pedestrian environments through small interventions and the day-to-day maintenance of public spaces. The citizen-science led method played an important role in highlighting the areas for improving urban walkability, with photographic evidence. Cross-examination with the results from other methods provided deeper insights into people’s perceptions of their walking environment and routes on a neighbourhood scale.