Above Helsinki’s streets, an impressive underground network connects metro stations, shopping malls, restaurants and important buildings, allowing people to get around without having to face the harsh Finnish winter. With over 400 meters of strategically planned passages, this infrastructure protects against temperatures that can drop below -20°C, as well as improving urban mobility and reducing surface traffic. In addition to the tunnels, Helsinki has invested in pedestrian and cyclist-friendly streets, ensuring year-round accessibility. This innovative approach demonstrates the city’s commitment to efficient transport, safety and sustainability, setting an example for urban planning for the world.