If you haven't played any of the other Impressions Games 'City Builder' series, do 100% play Caesar III as skozzii said, but after do continue on with the others. They made Caesar 1-3, then Pharaoh (plus an expansion), Zeus (plus an expansion), and Emperor: Rise of the Middle Kingdom, all based in Ancient Rome, Egypt, Greece, and China respectively. All of them are wonderful, yet a bit different in various ways (and I'd go so far so as to say most people would say Pharaoh is the best of them, though Zeus is fantastic as well). They also, after shutting down, went on to form Tilted Mill, which put out Caesar IV, and Immortal Cities: Children of the Nile, two 2 more city builders (also again, a bit different than before) before they also shut down. And all of them are also available on GOG, as a bonus.

'Course everything mentioned past Caesar II is beyond DOS but lol Still gonna recommend em!