An open sight for use on weapons such as handguns is disclosed. The open sight features two rear aiming marks mounted in the rear sight and a third aiming mark in the front sight. The aiming marks are illuminated by one or more artificial light sources disposed within the rear sight. The artificial light sources project light forward to the front sight and illuminate the rear aiming marks. The front sight is dimensioned to substantially block the forward directed beam to reduce the visibility of the illumination forward of the weapon.