  We study geometric engineering of four-dimensional N=1 gauge models from
M-theory on a seven-dimensional manifold with G_2 holonomy. The manifold is
constructed as a K3 fibration over a three-dimensional base space with ADE
geometry. The resulting gauge theory is discussed in the realm of (p,q) webs.
We discuss how the anomaly cancellation condition translates into a condition
on the associated affine ADE Lie algebras.
