On Helgoland you can find the so-called tetrapods which serve as coastal protection there. Weighing 7 tons each they can withstand the force of the water well._站酷海洛_正版图片_视频_字体_音乐素材交易平台

On Helgoland you can find the so-called tetrapods which serve as coastal protection there. Weighing 7 tons each they can withstand the force of the water well.