  We present the first analysis of preliminary data for $Pb+Pb$ at 160 $AGeV$
using 3+1-dimensional relativistic hydrodynamics. We find excellent agreement
with the rapidity spectra of negative hadrons and the correlation measurements.
The data indicates a large amount of stopping; $65\%$ of the invariant energy
of the collision is thermalized and $73\%$ of the baryons are contained in the
central fireball. Within our model this implies that a quark-gluon-plasma of
lifetime 3.4 $fm/c$ was formed.
