  Phase diagram of vortex states of high-$T_{\rm c}$ superconductors with {\it
sparse and weak} columnar defects is obtained by large-scale Monte Carlo
simulations of the three-dimensional anisotropic, frustrated XY model. The
Bragg-Bose glass phase characterized by hexagonal Bragg spots and the diverging
tilt modulus is observed numerically for the first time at low density of
columnar defects. As the density of defects increases, the melting temperature
increases owing to "selected pinning" of flux lines. When the density of
defects further increases, the transition to the Bose glass phase occurs. The
interstitial liquid region is observed between these two glass phases and the
vortex liquid phase.
