  We study the deflection of ultra high energy cosmic ray protons in different
models of the regular galactic magnetic field. Such particles have gyroradii
well in excess of 1 kpc and their propagation in the galaxy reflects only the
large scale structure of the galactic magnetic field. A future large
experimental statistics of cosmic rays of energy above 10$^{19}$ eV could be
used for a study of the large scale structure of the galactic magnetic field if
such cosmic rays are indeed charged nuclei accelerated at powerful
astrophysical objects and if the distribution of their sources is not fully
isotropic.
