  NGC 6369 is a double-shell planetary nebula (PN) consisting of a bright
annular inner shell with faint bipolar extensions and a filamentary envelope.
We have used ground- and space-based narrow-band optical and near-IR images,
broad-band mid-IR images, optical long-slit echelle spectra, and mid-IR spectra
to investigate its physical structure. These observations indicate that the
inner shell of NGC 6369 can be described as a barrel-like structure shape with
polar bubble-like protrusions, and reveal evidence for H2 and strong polycyclic
aromatic hydrocarbons (PAHs) emission from a photo-dissociative region (PDR)
with molecular inclusions located outside the bright inner shell.
High-resolution HST narrow-band images reveal an intricate excitation structure
of the inner shell and a system of "cometary" knots. The knotty appearance of
the envelope, the lack of kinematical evidence for shell expansion and the
apparent presence of emission from ionized material outside the PDR makes us
suggest that the envelope of NGC 6369 is not a real shell, but a flattened
structure at its equatorial regions. We report the discovery of irregular knots
and blobs of diffuse emission in low-excitation and molecular line emission
that are located up to 80" from the central star, well outside the main nebular
shells. We also show that the filaments associated to the polar protrusions
have spatial extents consistent with post-shock cooling regimes, and likely
represent regions of interaction of these structures with surrounding material.
