A LinearRing is defined by four or more coordinate tuples, with linear interpolation between them; the first and last coordinates shall be coincident. The number of direct positions in the list shall be at least four.
<element name="LinearRing" type="gml:LinearRingType" substitutionGroup="gml:AbstractRing"><annotation><documentation>A LinearRing is defined by four or more coordinate tuples, with linear interpolation between them; the first and last coordinates shall be coincident. The number of direct positions in the list shall be at least four.</documentation></annotation></element>