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We provided accurate estimates of distances, radii and iron abundances forfour metal-rich Cepheids, namely V340 Ara, UZ Sct, AV Sgr and VY Sgr. The mainaim of this investigation is to constrain their pulsation properties and theirlocation across the Galactic inner disk. We adopted new accurate NIR (J,H,K)light curves and new radial velocity measurements for the target Cepheids todeterminate their distances and radii using the Baade-Wesselink technique. Inparticular, we adopted the most recent calibration of the IR surface brightnessrelation and of the projection factor. Moreover, we also provided accuratemeasurements of the iron abundance of the target Cepheids. Current distanceestimates agree within one sigma with similar distances based either onempirical or on theoretical NIR Period-Luminosity relations. However, theuncertainties of the Baade-Wesselink distances are on average a factor of 3-4smaller when compared with errors affecting other distance determinations. MeanBaade-Wesselink radii also agree at one sigma level with Cepheid radii basedeither on empirical or on theoretical Period-Radius relations. Iron abundancesare, within one sigma, similar to the iron contents provided by Andrievsky andcollaborators, thus confirming the super metal-rich nature of the targetCepheids. We also found that the luminosity amplitudes of classical Cepheids,at odds with RR Lyrae stars, do not show a clear correlation with themetal-content. This circumstantial evidence appears to be the consequence ofthe Hertzsprung progression together with the dependence of the topology of theinstability strip on metallicity, evolutionary effects and binaries.

New Baade-Wesselink distances and radii for four metal-rich Galactic Cepheids