  Using many-body configuration interaction techniques we show that Wigner
crystallization occurs at the zigzag edges of graphene at surprisingly high
electronic densities up to $0.8$ $\mbox{nm}^{-1}$. In contrast with
one-dimensional electron gas, the flat-band structure of the edge states makes
the system interaction dominated, facilitating the electronic localization. The
resulting Wigner crystal manifests itself in pair-correlation functions, and
evolves smoothly as the edge electron density is lowered. We also show that the
crystallization affects the magnetization of the edges. While the edges are
fully polarized when the system is charge neutral (i.e. high density), above
the critical density, the spin-spin correlations between neighboring electrons
go through a smooth transition from antiferromagnetic to magnetic coupling as
the electronic density is lowered.
