This project consists in the corporate image transformation of the underground car parks managed by the municipal company of the Town Hall of Barcelona BSM (Barcelona Serveis Muncipals). A simple artistic painting intervention has made this transformation possible. Barcelona is a city in direct contact with the sea, influenced by the Mediterranean culture and with deep roots of its architecture and urbanism suggested by nature. The solution is inspired by the visual perception that we have when immersing under the sea and discover a new world of shapes and colours in the sea bottom. For the image change, we pretend that the vehicle and its occupants, when descending to the car park, could escape from the intensity and city pressure. Previously, this happened in dark car parks, organised under very strict engineering criteria and with a superposition of car park maintenance that resulted in the excess of traffic signals and commands to the driver.