A plan can take the form of a site location drawing, which places a site within a larger map of an area to locate a building or proposal. The plan drawing allows an understanding of entrances, access, and movement across or through a site, as well as important adjacent locations and adjacent buildings or structures. A plan should indicate orientation, so a north point is essential. It is the convention for plans to be oriented so that north points upward on the page, although sometimes this is not possible. When gridlines are used, they are normally indicated with north to the top of the page.