A custom house or customs house was traditionally a building housing the offices for a jurisdictional government whose officials oversaw the functions associated with importing and exporting goods into and out of a country, such as collecting customs duty on imported goods. A custom house was typically located in a seaport or in a city on a major river, with access to an ocean. These cities acted as ports of entry into a country.
Due to advances in electronic information systems, the increased volume of international trade, and the introduction of air travel, custom houses have largely become obsolete. Many custom houses around the world have since been converted for other uses, such as museums or civic buildings.