hexagonal basalt rocks at hljodaklettar on iceland

hljodaklettar day sunny summer park national japara kulsaiexcl aiexcl fjapara llum ravine gorge river valley grey black mineral surface gray volcano rock pattern hexagonal hexagon erosion canyon tourism dramatic peak pinnacle stone iceland basalt geology nature natural landscape volcanic column texture scandinavia jokulsargljufur lava cliff icelandic beautiful vesturdalur cave formation rosette organ