Ball Pyramid - the world’s tallest sea stack. It is the remains of a shield volcano formed about 7 million years ago, located southeast of Lord Howe Island in the Pacific Ocean. Ball's Pyramid is part of the Lord Howe Island Marine Park in Australia.
Salt Cathedral of Zipaquirá. an underground Roman Catholic church built within the tunnels of a salt mine 200 meters underground in a Halite mountain near the town of Zipaquirá, in Cundinamarca, Colombia.