Have you ever seen a pier? It's like a long pathway that goes out into a body of water like a lake or an ocean. Well, an ice pier is just like a pier, but it's made of ice instead of wood or metal.
In really cold places, like the Arctic or Antarctic, the water can freeze solid and become ice. When this happens, people sometimes need to build a pathway out onto the ice so they can get to boats or other things on the ice.
So, when someone needs to get to those things, they build an ice pier by scraping away the snow and creating a flat surface. They might also use machines to pack down the snow and create a hard surface. Then, they pour water on the surface to freeze and make it stronger. This creates a safe pathway that people can walk on to get to their boats or other things on the ice.
Just like a regular pier, an ice pier helps people walk over the surface of the water without getting wet or falling in.