  Galactic starburst clusters play a twin role in astrophysics, serving as
laboratories for the study of stellar physics and also delineating the
structure and recent star formation history of the Milky Way. In order to
exploit these opportunities we have undertaken a multi-epoch spectroscopic
survey of the red supergiant dominated young massive clusters thought to be
present at both near and far ends of the Galactic Bar. Significant
spectroscopic variability suggestive of radial pulsations was found for the
yellow supergiant VdBH 222 #505. Follow-up photometric investigations revealed
modulation with a period of ~23.325d; both timescale and pulsational profile
are consistent with a Cepheid classification. As a consequence #505 may be
recognised as one of the longest period Galactic cluster Cepheids identified to
date and hence of considerable use in constraining the bright end of the
period/luminosity relation at solar metallicities. In conjunction with extant
photometry we infer a distance of ~6kpc for VdBH222 and an age of ~20Myr. This
results in a moderate reduction in both integrated cluster mass (~2x10^4Msun)
and the initial stellar masses of the evolved cluster members (~10Msun). As
such, VdBH222 becomes an excellent test-bed for studying the properties of some
of the lowest mass stars observed to undergo type-II supernovae. Moreover, the
distance is in tension with a location of VdBH 222 at the far end of the
Galactic Bar. Instead a birthsite in the near 3kpc arm is suggested; providing
compelling evidence of extensive recent star formation in a region of the inner
Milky Way which has hitherto been thought to be devoid of such activity.
