This paper discusses site selection criteria for a Moon‐based observatory, using an area on the NE flank of the Orientale Basin at 80° W on the lunar equator as a recommended example. Such a site would provide the following advantages: visibility of essentially the entire celestial sphere, continual line of sight to Earth, dynamic accessibility for minimum energy landings and takeoffs, closeness to the far side for installation of instruments requiring a radio silent environment, trafficable and workable terrain, closeness to geologically important features, and closeness to volcanic features with potential resources. Polar and far side sites have advantages as well, and no one site can meet all requirements. It is suggested that other candidate sites be evaluated by the criteria used for the Orientale Basin.