The basic land "unit" in the State of Minnesota is a "section". In theory a section is meant to be a square mile; one mile long on each side and 90 degrees in all four corners. In actuality there are no sections, especially in northeastern Minnesota where terrain is rugged, that meet that criteria. Like snowflakes, no two sections are exactly the same. Some are short, some are long, and most of them lean either east or west. When the original surveyors laid out the sections in the 1800s they did their best but it was an impossible task. Therefore, before the interior can be surveyed, the dimensions of the whole box must first be determined, i.e. the section must be "broken down". That is, the exterior section lines must be established correctly. Once this is done, the interior forty lines of a section can be laid out. There are many sections in northeastern Minnesota for which there is no breakdown available.