  We briefly report on a previously found new, approximate, solution to
Einstein field equations, describing a cubic lattice of spherical masses. This
model mimics in a satisfactory way a Universe which can be strongly
inhomogeneous at small scales, but quite homogeneous at large ones. As a
consequence of field equations, the lattice Universe is found to expand or
contract in the same way as the solution of a Friedmann Universe filled with
dust having the same average density. The study of observables indicates
however the possible existence of a fitting problem, i.e. the fact that the
Friedmann model obtained from past-lightcone observables does not match with
the one obtained by smoothing the matter content of the Universe.
