In this paper we formulate an integrable model on the simple cubic lat
tice. The N-valued spin variables of the model belong to edges of the
lattice. The Boltzmann weights of the model obey The vertex-type tetra
hedron equation. In the thermodynamic limit our model is equivalent to
the Bazhanov-Baxter model. In the case when N=2 we reproduce Korepano
v's and Hietarinta's solutions of the tetrahedron equation as special
cases.