The document is a slideshow that provides nighttime views of various cities and locations around the world. By clicking, the viewer can add color to the black and white slides and advance to the next image, which includes cities like Frankfurt, Bremerhaven, Hamburg, Sydney, Berlin, Budapest, Cologne, London, Prague, Dresden, Salzburg, Las Vegas, Venice, Mount Saint-Michel, Paris, Tokyo, Shanghai, Hong Kong, Kuala Lumpur, the Alps, Moscow, and images of the Tower Bridge and its tower.