  We present here a new major part of the OGLE Collection of Variable Stars -
OGLE Collection of Galactic Cepheids. The new dataset was extracted from the
Galaxy Variability Survey images - a dedicated large-scale survey of the
Galactic disk and outer bulge conducted by the OGLE project since 2013.
  The OGLE collection contains 2721 Cepheids of all types - classical, type II
and anomalous. It more than doubles the number of known Galactic classical
Cepheids. Due to the long-term monitoring and large number of epochs the
selected sample is very pure, generally free from contaminating stars of other
types often mimicking Cepheids. Its completeness is high at 90% level for
classical Cepheids - tested using recent samples of Galactic Cepheids: ASAS-SN,
ATLAS, Gaia DR2 and Wise catalog of variable stars. Our comparisons indicate
that the completeness of the two latter datasets, Gaia DR2 and Wise catalog, is
very low, at < 10% level in the magnitude range of the OGLE GVS survey (10.8 <
I < 19.5 mag). Both these samples are severely contaminated by non-Cepheids
(the purity is 67% and 56%, respectively).
  We also present several interesting objects found in the new OGLE Collection
- multi-mode pulsators, a first Galactic candidate for eclipsing system
containing Cepheid, a binary Cepheid candidate.
