How is the night in a city? Why is it different from the day? What about the dark hours within the life of places? Can they enlighten our (human) thoughts? Night time is another layer of cities: lights and shadows.We go for a night stroll. We wander in a city invaded by mass tourism, where the night tours look for music, monuments, typical food and neighbourhoods, parties, drinks, sex. We propose to discover those details that are unique in a city night space and time (because they do not exist during the day). We will look at the beauty and richness of city spaces at night. We will capture night light phenomena: shadows, reflections, sparkling effects, traffic lights, glary lights, invisible sources, wandering thoughts. With connected devices, phones, cameras...and machine learning. The use of social media to share photos, night visions and other thoughts by humans, will enhance creative machine learning and will have a broader impact in the development of architecture in the future.