BlueCity is an international icon of circular economy, an international platform for circular entrepreneurs, and a very visible local accelerator that empowers circular entrepreneurs and inspires citizens. Situated in the former subtropical swimming oasis Tropicana in Rotterdam, we saved the building from being demolished and transformed it as circular as possible. Re-using old elements and materials both from within the swimming pool as from other abandoned buildings, turning this pool into a playground for circular entrepreneurs where brains, guts, vision and fun go together. Together we work on an economy in which waste does not exist. Inside our ecosystem of social entrepreneurs and radical disruptors waste streams are valuable building blocks; the output of one is the input for the other. This way we create a much needed and inspiring example for the circular economy.