Global health and climate benefits from walking and cycling infrastructure

We use a globally consistent dataset-Google Environmental Insights Explorer-to quantify how urban form and transport infrastructure affect walking and cycling rates in 11,587 cities from 121 countries across six continents. At the city level, population density has the largest effect on walk mode share and has a positive impact on cycling too, as higher densities bring destinations within feasible walk and cycle distances. Density has the strongest effects in wealthier countries where travelers often have more travel choices, while in lower-income places, walking and cycling may be primarily driven by financial constraints. We also find positive effects of bicycle lanes (proxying for a wider array of street design practices) on both walking and cycling. In the median city, each new km of bicycle lanes is associated with ~13,400 additional km yr^-1 of bicycle travel. If every city increased the extent of its bicycle network to the level of Copenhagen, Denmark, our simulations indicate reductions in private vehicle emissions of ~6% and health benefits of ~US$435 billion per year.