The open cluster NGC 6791 is now considered both the oldest and the most metal-rich known. Its age is 8 -10 Gyrs, twice as old as the canonical solar-metallicity cluster M67 (Garnavich et al. 1994; Demarque, Green, & Guenther 1992; Tripicco et al. 1995). That its metallicity is significantly above solar is suggested from moderate-resolution spectroscopy and from a mismatch of its color-magnitude diagram (CMD) with solar-metallicity isochrones. Tripicco et al. (1995) find Fe/H] = +0.27 to +0.44. The cluster population is rich. In addition to about a dozen red giants and two dozen red...