  Cosmic rays (CRs) are charged particles that arrive at Earth isotropically
from all directions and interact with the atmosphere. The presence of a
spectral knee feature seen in the CR spectrum at $\sim$3 PeV energies is an
evidence that astrophysical objects within our Galaxy, which are known as
'Galactic PeVatrons', are capable of accelerating particles to PeV energies.
Scientists have been trying to identify the origin of Galactic CRs and have
been looking for signatures of Galactic PeVatrons through neutral messengers.
Recent advancements in ground-based $\gamma$-ray astronomy have led to the
discovery of 12 Galactic sources emitting above 100 TeV energies, and even the
first time detection of PeV photons from the direction of the Crab Nebula and
the Cygnus region. These groundbreaking discoveries have opened up the field of
ultra-high energy (UHE, E$>$100 TeV) $\gamma$-ray astronomy, which can help us
explore the high energy frontiers of our Galaxy, hunt for PeVatron sources, and
shed light on the century-old problem of the origin of CRs. This review article
provides an overview of the current state of the art and potential future
directions for the search for Galactic PeVatrons using ground-based
$\gamma$-ray observations.
