A boat berth is a place where a boat can be moored or docked. It is also known as a PIER, which is the four-letter solution to this crossword puzzle. A boat berth is typically a structure built out into a body of water, such as a lake or ocean, and provides a safe place for a boat to be secured. It is often made of wood, concrete, or steel and may include amenities such as electricity, water, and fuel.