To facilitate the adoption of community-based practices for active ageing, it is important to design these practices together with a wide range of older adults from the community via an interdisciplinary perspective. Hackathons, originally developed by programmers, have been adapted by different disciplines and started to include a wide range of users and stakeholders. We aim to investigate how to conduct an intergenerational and interdisciplinary hackathon to support community-based co-design with older adults. In this case study, an intergenerational and interdisciplinary hackathon was organised together with a senior centre in the Netherlands. Semi-structured interviews were conducted to understand the experiences of participants and how they think the hackathon could be improved. Participants’ positive experiences were categorised into five themes, and six areas for improvement were specified. The findings were discussed in relation to recent literature, and a list of future research directions was proposed to inspire future researchers interested in this topic.