  We establish the scalar curvature and distance bounds, extending Perelman's
work on the Fano K\"ahler-Ricci flow to general finite time solutions of the
K\"ahler-Ricci flow. These bounds are achieved by our Li-Yau type and Harnack
estimates for weighted Ricci potential functions of the K\"ahler-Ricci flow. We
further prove that the Type I blow-ups of the finite time solution always
sub-converge in Gromov-Hausdorff sense to an ancient solution on a family of
analytic normal varieties with suitable choices of base points. As a
consequence, the Type I diameter bound is proved for almost every fibre of
collapsing solutions of the K\"ahler-Ricci flow on a Fano fibre bundle. We also
apply our estimates to show that every solution of the K\"ahler-Ricci flow with
Calabi symmetry must develop Type I singularities, including both cases of high
codimensional contractions and fibre collapsing.
