<http://schema.org/alternativeHeadline>
"Google Night Walk is an immersive tour of Marseille with Street View photos and an audio guide"^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/google/2014/04/04/google-night-walk-immersive-tour-marseille-street-view-photos-audio-guide/>