  We present and study the largest and the most comprehensive catalog of
microlensing events ever constructed. The sample of standard microlensing
events comprises 3718 unique events from years 2001--2009, with 1409 not
detected before in real-time by the Early Warning System of the Optical
Gravitational Lensing Experiment (OGLE). The search pipeline makes use of
Machine Learning algorithms in order to help find rare phenomena among 150
million objects and derive the detection efficiency. Applications of the
catalog can be numerous, from analyzing individual events to large statistical
studies for the Galactic mass and kinematics distributions and planetary
abundances.
  We derive the maps of the mean Einstein ring crossing time of events spanning
31 sq. deg. toward of the Galactic Center and compare the observed
distributions with the most recent models. We find good agreement within the
observed region and we see the signature of the tilt of the bar in the
microlensing data. However, the asymmetry of the mean time-scales seems to rise
more steeply than predictions, indicating either a somewhat different
orientation of the bar or a larger bar width. The map for the events with
sources in the Galactic bulge shows a dependence of the mean time-scale on the
Galactic latitude, signaling an increasing contribution from disk lenses closer
to the plane, related with the height of the disk. Our data present a perfect
set for comparing and enhancing new models of the central parts of the Milky
Way and creating the 3D picture of the Galaxy.
