raised structure in a body of water, typically supported by well-spaced piles or pillars

A pier is a raised walkway across water. It can be a simple light wooden structure which has no effect on the current and tides, or a major structure with buildings and as long as a mile out to sea. In the United States, these may be referred to as docks. A pier can be made of wood, concrete, or other materials.

An example of a pier in New Zealand