Dykes are a familiar (albeit manmade) feature of the Dutch landscape. Running parallel to rivers or the sea, they play a crucial role in flood prevention. But what role can they play in helping control the complex and sometimes suffocating hot urban climate? In recent years, city dwellers have been hit by a phenomenon known as urban heat island (UHI). This occurs when a metropolitan area is significantly warmer than surrounding rural areas due to the topography of the city and human activity. Climate change and urbanisation mean that the incidence of UHIs is on the rise and we urgently need to find ways to cool the urban space. Thermal-driven winds between floodplains and built-up areas offer great potential when it comes to urban heat mitigation. But these winds move very slowly – and just above ground level. In order to invite the cool breeze into Dutch cities, dykes – that currently play the role of a barrier – need to be re-analysed and redesigned to serve a multifunctional purpose.