large hverfjall volcano crater is tephra cone or tuff ring volcano on gloomy day in myvatn area at iceland

aerial view black cone countryside crater dark destination difficulty dirty eruption europe geology gloomy hiking horizontal hverfjall iceland icelandic inactive island landscape large majestic moody mountain myvatn natural nature north overcast rock rough scandinavia scenery scenic shape sightseeing sky tephra top tourism travel trekking trip vacation volcanic volcano wilderness