Urban green spaces provide important recreational, social and psychological benefits to stressed city residents. This paper aims to understand the importance of parks for visitors. We focus on Delhi, the world’s second most populous city, drawing on 123 interviews with park visitors in four prominent city parks. Almost all respondents expressed the need for more green spaces. Visitors valued parks primarily for environmental and psychological/health benefits. They had limited awareness of biodiversity, with one out of three visitors unable to identify tree species and one out of four visitors unable to identify animal species frequenting the park. Most of the daily visitors lived within 0.5 km of these parks, but a small fraction of visitors traveled over 10 km to visit these major parks, despite having smaller neighbourhood parks in their vicinity. This study demonstrates the importance of large, well-maintained, publicly accessible parks in a crowded city. The results can help to better plan and design urban green spaces, responding to the needs and preferences of urban communities. This research contributes to the severely limited information on people’s perceptions of and requirements from urban nature in cities of the Global South.