The Ball Pyramid Pacific Ocean

The Ball Pyramid is the world's tallest  and the largest sea stack. It is the remains of a shield volcano formed about 7 million years ago. It is 562 meters high and is located southeast of Lord Howe Island in the Pacific Ocean.
Ball's Pyramid is an erosional remnant of a shield volcano and caldera that formed about 7 million years ago. Ball's Pyramid is 20 kilometres (12 mi) southeast of Lord Howe Island in the Pacific Ocean. It is 562 metres (1,844 ft) high, while measuring only 1,100 metres (3,600 ft) in length and 300 metres (980 ft) across, making it the tallest volcanic stack in the world. Ball's Pyramid is part of the Lord Howe Island Marine Park in Australia.

Ball's Pyramid has a few satellite islets. Observatory Rock and Wheatsheaf Islet lie about 800 metres (2,600 ft) west-northwest and west-southwest respectively, of the western extremity of Ball's Pyramid. Southeast Rock is a pinnacle located about 3.5 kilometres (2.2 mi) southeast of Ball's Pyramid. Like Lord Howe Island and the Lord Howe seamount chain, Ball's Pyramid is based on the Lord Howe Rise, part of the submerged continent of Zealandia.

Source:-Wikipedia