Intermediate-age open clusters: Collinder 110

We present CCD BV photometry of the intermediate-age open cluster Collinder 110, a nearby, scarcely populated and poorly studied system. There is no literature information about the metallicity, so we tested several possibilities and found slight evidence of subsolar abundances. Using the synthetic colour-magnitude diagrams (CMDs) technique, we estimate the following parameters: age between 1.1 and 1.5 Gyr, reddening 0.38less than or equal toE (B-V)less than or equal to0.45 and distance modulus (m-M)(0) between 11.8 and 11.9, if the cluster metallicity is solar; or age between 1.2 and 1.7 Gyr, reddening 0.52less than or equal toE(B-V)less than or equal to0.57 and distance modulus (m-M)(0) between 11.45 and 11.7, if the cluster metallicity is subsolar.