umi jigoku - boiling blue sea hell, beppu, japan. one of eight hot springs. attractions known for their unique natural appearances

chinoike jigoku hell pond beppu onsen japan blood colored water color temperature japanese hot steam colorful colour coloured asia asian mineral umi sea beppu's seven 'hells' renowned spring attractions unique natural appearances hells 98° blue eight springs pool boiling one umi-jigoku created volcanic explosion tsurumidake mountain 1200 years famous sea-blue cobalt large amount iron oxide degrees high