  The minimal length of ``one-dimensional'' Josephson junctions, in which the
specific bound states of the magnetic flux retain their stability is discussed
numerically. Thereby, we consider as ``long'' every Josephson junction, in
which there exists at least one nontrivial stable distribution of the magnetic
flux for fixed values of all the physical and the geometrical parameters.
  Our results can be applied for optimization of the sizes of devices
containing Josephson junctions for different operating conditions.
