  Eruptions of classical novae are possible sources of lithium formation and
gamma-ray emission. Nova remnants can also become Type Ia supernovae (SNe Ia).
The contribution of novae to these phenomena depends on nova rates, which are
not well established for the Galaxy. Here, we directly measure a Galactic bulge
nova rate of $13.8 \pm 2.6$ per year. This measurement is much more accurate
than any previous measurement of this kind thanks to many years' monitoring of
the bulge by the Optical Gravitational Lensing Experiment (OGLE) survey. Our
sample consists of 39 novae eruptions, $\sim$1/3 of which are OGLE-based
discoveries. This long-term monitoring allows us to not only measure the nova
rate but also to study in detail the light curves of 39 eruptions and more than
80 post-nova candidates. We measured orbital periods for 9 post-novae and 9
novae, and in 14 cases we procured the first estimates. The OGLE survey is very
sensitive to the frequently erupting recurrent novae. We did not find any
object similar to M31 2008-12a, which erupts once a year. The lack of detection
indicates that there is only a small number of them in the Galactic bulge.
