  HESS J1809$-$193 is one of the unidentified very-high-energy gamma-ray
sources in the H.E.S.S. Galactic Plane Survey (HGPS). It is located in a rich
environment, with an energetic pulsar and associated X-ray pulsar wind nebula,
several supernova remnants, and molecular clouds in the vicinity. Furthermore,
HESS J1809$-$193 was recently detected at energies above 56 TeV with HAWC,
which makes it a PeVatron candidate, that is, a source capable of accelerating
cosmic rays up to PeV energies. We present a new analysis of the TeV gamma-ray
emission of HESS J1809$-$193 with H.E.S.S., based on improved analysis
techniques. We find that the emission is best described by two components with
distinct morphologies and energy spectra. We complement this study with an
analysis of Fermi-LAT data in the same region. Finally, taking into account
further multi-wavelength data, we interpret our results both in a hadronic and
leptonic framework.

High Energy Astrophysical Phenomena