Context : 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 .

Aims : In order to exploit these opportunities we have undertaken a spectroscopic survey of the red supergiant dominated young massive clusters thought to be present at both near and far ends of the Galactic Bar .

Methods : Specifically , multi-epoch observations were employed to identify and investigate stellar variability and its potential role in initiating mass loss amongst the cool super-/hypergiant populations of these aggregates .

Results : 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 \sim 23.325 d ; both timescale and pulsational profile are consistent with a Cepheid classification .

Conclusions : # 505 is 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 \sim 6 kpc for VdBH222 and an age of \sim 20 Myr .
This results in a moderate reduction in both the integrated cluster mass ( \sim 2 \times 10 ^ { 4 } M _ { \odot } ) and the initial masses of the evolved cluster members ( \sim 10 M _ { \odot } ) .
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 .