World Cities Day brings Urban October to an end on 31 October each year and was first celebrated in 2014. As with World Habitat Day, a global observance is held in a different city each year and the day focuses on a specific theme.

On 31 October 2023, the Global Observance of World Cities Day, under the theme Financing sustainable urban future for all, explored how we can unlock transformative investment in urban planning and achieve adequate fiscal decentralization.