+A heptagon is a [Polygon](/wiki/polygon) defined by seven straight sides and seven vertices. The sum of its interior angles is always 900 degrees. A regular heptagon, with all sides and [Angle](/wiki/angle)s equal, possesses a unique seven-fold symmetry.
+## See also
+- [Hexagon](/wiki/hexagon)
+- [Octagon](/wiki/octagon)
+- [Shape](/wiki/shape)
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