We report on deep ( V \approx 24.0 ) VI CCD photometry of 3 fields centered in the regions of the old open clusters Saurer A , B and C. In the case of Saurer A , which is considered one of the oldest known open cluster , we also provide a comparison field .
From the analysis of the photometry we claim that Saurer A is as old as M 67 ( \approx 5 Gyrs ) , but more metal poor ( Z=0.008 ) .
Moreover it turns out to be the open cluster with the largest galactocentric distance so far detected . As for Saurer B , it closely resembles NGC 2158 , and indeed is of intermediate-age ( 1.8-2.2 Gyrs ) and significantly reddened .
In this case we revise both the age and the distance with respect to previous studies , but we are not able to clearly establish the cluster metal abundance . Finally , Saurer C has an age of about 2 Gyrs , but we emphasize that the precise determination of its properties is hampered by the heavy field stars contamination .