Constructing a tridecagon (triskaidecagon) in a circumcircle with ruler and compass

It¬ possible to construct a regular 13 sided polygon (tridecagon or triskaidecagon) using a straightedge and a compass. However, you can get so close that you won&be able to see the difference. This video shows you how. The polygon gets (almost) constructed inside a given circle, that becomes the circumcircle of the polygon.