U.S. Custom House

Constructed in 1836, the U.S. Custom House in New Bedford holds the distinction of being the oldest continual-use custom house in the nation and was designed by renowned architect Robert Mills. Mills is credited with designing many of Washington D.C.'s historic sites, including the U.S. Treasury, the General Post Office, the Patent Office, and the Washington Monument. In the whaling era, whaling masters would come to the custom house to register their ships and cargo. Today, commercial fishing and cargo ships continue to log duties and tariffs there.

Information courtesy the National Park Service - https://www.nps.gov/nr/travel/maritime/usc.htm