<http://schema.org/keywords>
"apocalyptic, hokkaido, Hokkaido_Feb2012, japan, mbp, rocks, rocky, rugged, steam, sulphur, volcanic, volcanic steam, volcano, winter, yellow"^^<http://www.w3.org/2001/XMLSchema#string>
<https://marketplace.500px.com/photos/5746435/apocalyptic-by-martin-bailey>