The Berlin Cathedral illuminated during the Festival of Lights in Berlin, Germany

The Berlin Cathedral illuminated during the Festival of Lights in Berlin, Germany

The domes of the Berlin Cathedral are already worth a photo during a visit to the German capital. But every year since 2004, October brings the Festival of Lights to Berlin and many iconic structures in the city become canvases for artists using light as a medium. From digital projections like those on the cathedral, to lasers, neon, and other light-generating devices, Berlin will be aglow for the next 10 nights. Best of all, the show is free—simply grab a map of all the light shows and start walking.