  In this paper we consider a new approach to studying Kundt spacetimes through
$G$-structures. We define a Lie-group $GN$ such that the $GN$-structures
satisfying an integrability condition and an existence criterion, which we call
Kundt structures, have the property that each metric belonging to the Kundt
structure is automatically a Kundt spacetime. We find that the Lie algebra of
infinitesimal automorphisms of such structures is given by a Lie algebra of
nil-Killing vector fields. Lastly we characterize all left invariant Kundt
structures on homogeneous manifolds.
