Twin cities refer to two neighboring cities or urban centers that grow into a single conurbation or narrowly separated urban areas over time. There are no formal criteria, but twin cities are generally two cities that share many of the same political, educational, and cultural institutions and are thus considered to be "twins". The most common usage of the term "Twin Cities" refers to Minneapolis and St. Paul, which are the two largest cities in Minnesota and are located next to each other. However, the term can also refer to other pairs of cities around the world that share a special relationship, such as trade or cultural ties. In some cases, the term "Twin Cities" may also be used to refer to the broader metropolitan area that includes the two cities and their surrounding suburbs.