A wharf is a fixed platform, commonly on pilings, roughly parallel to and alongside navigable water, where ships are loaded and unloaded. A pier extends perpendicular to the shore.
Derby (1762), Hatch's (1819) and Central (1791) Wharves in Salem, Massachusetts are the last of the 50 wharves which lined Salem harbor. They are part of the Salem Maritime National Historic Site, the only remaining intact waterfront from the US age of sail. In 1790, Salem was the sixth largest city in the country.