  This work is mainly devoted to constructing a multisymplectic description of
Lovelock's gravity, which is an extension of General Relativity. We establish a
Griffiths variational problem for the Lovelock Lagrangian, obtaining the
geometric form of the corresponding field equations. We give the unified
Lagrangian--Hamiltonian formulation of this model and we study the
correspondence between the unified formulations for the Einstein--Hilbert and
the Einstein--Palatini models of gravity.
