  Dust and stars in the plane of the Milky Way create a "Zone of Avoidance" in
the extragalactic sky. Galaxies are distributed in gigantic labyrinth
formations, filaments and great walls with occasional dense clusters. They can
be traced all over the sky, except where the dust within our own galaxy becomes
too thick - leaving about 25% of the extragalactic sky unaccounted for. Our
Galaxy is a natural barrier which constrains the studies of large-scale
structures in the Universe, the peculiar motion of our Local Group of galaxies
and other streaming motions (cosmic flows) which are important for
understanding formation processes in the Early Universe and for cosmological
models. Only in recent years have astronomers developed the techniques to peer
through the disk and uncover the galaxy distribution in the Zone of Avoidance.
I present the various observational multi-wavelength procedures (optical, far
infrared, near infrared, radio and X-ray) that are currently being pursued to
map the galaxy distribution behind our Milky Way. Particular emphasis is given
to discoveries in the Great Attractor region -- a from streaming motions
predicted huge overdensity centered behind the Galactic Plane. The recently
unveiled massive rich cluster A3627 seems to constitute the previously
unidentified core of the Great Attractor.

Astrophysics