The transportation impacts of an increasingly urban population have led planners and policy makers to consider ways to encourage the use of active travel in urban areas. Active travel is attractive from a planning perspective because its environmental impact is considerably lower than the alternatives, and in addition is known to have a number of population health and social benefits. Not surprisingly, there has been a growth in interest in the factors associated with the use of active modes of transportation. The objective of this study is to investigate the individual (demographic and socioeconomic) and contextual (geography and land use type) factors that correlate with the propensity to travel by active modes in Vitoria-Gasteiz. This is a medium sized city in the north of Spain, and a case study that has hitherto not been reported. Data obtained from a household travel survey (HTS) conducted in 2014 allow us to estimate a multinomial logit model of the propensity to travel by different modes of transportation. Furthermore, since the data are geocoded, we can estimate a model with spatially-varying coefficients to assess the geographical variations in the probability to use active modes. The results of the study provide valuable information concerning differences in active travel by gender and age, including significant and quite substantial variations by location. In addition, the effect of different urban fabrics indicates the relevance of density and mix of uses for active travel. In this way, the present research helps to increase our global knowledge-base regarding active travel in a medium-sized city. (Christiansen et al., 2016; Kim and Macdonald, 2016). Active modes do not contribute to greenhouse emissions, noise, or contamination, and do not rely extensively on non-renewable resources. As such, active forms of travel are the only truly sustainable transportation modes. Furthermore, active modes are accessible to the majority of the population, regardless of their income level (Pucher and Buehler, 2008; International Transport Forum, 2012), and walking in particular is recommended as a suitable form of transportation for people of all ages (US Department of Health and Human Services and others, 2008). Walking, in fact, is a fundamental mode in intermodal travel chains, since every trip begins and ends by walking, and it is also an important source of accessibility on its own right (Litman, 2003). Walking and cycling for transportation can also contribute to daily physical activity (Moniruzzaman et al., 2014; De Hartog et al., 2010), and therefore can also yield important health benefits by helping to reduce the risk of diseases such as cardiovascular disease, diabetes, some cancers, and