<http://schema.org/keywords>
"landscape, sunset, color, abstract, colour, horizon, art, 2012, 550d, fotografie, lek, lucht, rivier"^^<http://www.w3.org/2001/XMLSchema#string>
<https://marketplace.500px.com/photos/18253459/sunset-by-the-river-by-joost-lagerweij>