  The ANTARES high energy neutrino telescope is a three-dimensional array of
about 900 photomultipliers distributed over 12 mooring lines installed in the
Mediterranean Sea. Between February and November 2007 it acquired data in a
5-line configuration. The zenith angular distribution of the atmospheric muon
flux and the associated depth-intensity relation are measured and compared with
previous measurements and Monte Carlo expectations. An evaluation of the
systematic effects due to uncertainties on environmental and detector
parameters is presented.
