  We have obtained multi-object spectroscopy of luminous blue supergiants in
NGC 3109, a galaxy at the periphery of the Local Group at ~1.3 Mpc. We present
a detailed catalog including finding charts, V and I magnitudes, spectral
classifications, and stellar radial velocities. The radial velocities are seen
to trace the rotation curves obtained from studies of the HI gas. From
quantitative analysis of eight B-type supergiants we find a mean oxygen
abundance of 12+log(O/H) = 7.76 +/-0.07 (1-sigma systematic uncertainty), with
a median result of 7.8. Given its distance, we highlight NGC 3109 as the ideal
example of a low metallicity, dark-matter dominated, dwarf galaxy for
observations with the next generation of ground-based extremely large
telescopes (ELTs).
