  Longitudinal hydrodynamic expansion of the fluid created in relativistic
heavy-collisions is considered taking into account shear viscosity. Both a
on-vanishing viscosity and a soft equation of state make particle distributions
in rapidity narrower. The presence of viscosity has dramatic consequence on the
value of the initial energy density. The reduction of the longitudinal work and
dissipative processes due to the shear viscosity, increase the total entropy
and the particle multiplicity at central rapidities. The total energy in the
collision, dominated by the longitudinal motion, is conserved. Viscous
corrections make the longitudinal velocity of the fluid to stay close to the
Bjorken scaling v_z = z/t through the evolution. At the freeze-out viscous
corrections are the strongest for non-central rapidities.
