One of the most unique Metro systems in the world, Stockholm’s Tunnelbana is a work of art throughout. Many stations are designed to resemble deep, rocky caverns and have been painted in bright colors by a wide array of local artists, and the system has been dubbed the “World’s Longest Art Gallery.” Captured late at night and in the early hours of the morning, I’ve eliminated all people from the photos to focus on the unique art found along the system’s cave-like stations.