  We present the first imaging X-ray observation of the highly inclined (i = 78
deg) Sab Seyfert 2 galaxy NGC 6810 using XMM-Newton, which reveals soft X-ray
emission that extends out to a projected height of ~7 kpc away from the plane
of the galaxy. The soft X-ray emission beyond the optical disk of the galaxy is
most plausibly extra-planar, although it could instead come from large galactic
radius. This extended X-ray emission is spatially associated with diffuse
H-alpha emission, in particular with a prominent 5-kpc-long H-alpha filament on
the north-west of the disk. A fraction <~35% of the total soft X-ray emission
of the galaxy arises from projected heights |z| > 2 kpc. Within the optical
disk of the galaxy the soft X-ray emission is associated with the star-forming
regions visible in ground-based H-alpha and XMM-Newton Optical Monitor near-UV
imaging. The temperature, super-Solar alpha-element-to-iron abundance ratio,
soft X-ray/H-alpha correlation, and X-ray to far-IR flux ratio of NGC 6810 are
all consistent with local starbursts with winds, although the large base radius
of the outflow would make NGC 6810 one of the few ``disk-wide'' superwinds
currently known. Hard X-ray emission from NGC 6810 is weak, and the total
E=2-10 keV luminosity and spectral shape are consistent with the expected level
of X-ray binary emission from the old and young stellar populations. The X-ray
observations provide no evidence of any AGN activity. We find that the optical,
IR and radio properties of NGC 6810 are all consistent with a starburst galaxy,
and that the old classification of this galaxy as a Seyfert 2 galaxy is
probably incorrect.
