<http://schema.org/keywords>
"nikon d700, Nikkor 24-70 mm f/2.8, germany, cologne, koln, long exposure, rhine, dom, cathedral, lightbeams, architecture, january, skyline, night, misty, panoramic, river bank, north rhine-westphalia, fog, cityscape, altstadt, Rhine region, Allard Schager, Cologne, Germany"^^<http://www.w3.org/2001/XMLSchema#string>
<https://marketplace.500px.com/photos/19540345/k%25C3%25B6ln-altstadt-by-allard-schager>