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We construct general anisotropic cosmological scenarios governed by an $f(R)$gravitational sector. Focusing then on Kantowski-Sachs geometries in the caseof $R^n$-gravity, and modelling the matter content as a perfect fluid, weperform a detailed phase-space analysis. We find that at late times theuniverse can result to a state of accelerating expansion, and additionally, fora particular $n$-range ($2<n<3$) it exhibits phantom behavior. Furthermore,isotropization has been achieved independently of the initial anisotropydegree, showing in a natural way why the observable universe is so homogeneousand isotropic, without relying on a cosmic no-hair theorem. Moreover,contracting solutions have also a large probability to be the late-time statesof the universe. Finally, we can also obtain the realization of thecosmological bounce and turnaround, as well as of cyclic cosmology. Thesefeatures indicate that anisotropic geometries in modified gravitationalframeworks present radically different cosmological behaviors comparing to thesimple isotropic scenarios.

Dynamics of the anisotropic Kantowsky-Sachs geometries in $R^n$ gravity