Avalon Hill (AH) made great board games... but the upkeep between turns to keep things running was a LOT. AH was simply ahead of it's time; it NEEDED a computer to run all of the background stuff so you could just enjoy the game.
Enter Advanced Civilization. I have only kept a few CDs from way back when... and this is a forever game for me. Strategy without rolling. You build, you gain power, but the bigger you get the bigger the target. You get knocked down but are never out. And the trading mechanic that everyone loves so much in Cataan... IT STARTED HERE. Except here it's even better because of the disaster cards that can be traded (and of course, you also acquire disaster cards that you can't trade away). Your empire is constantly in flux, but relief is found in acquiring new technologies. So that famine that used to set you back? Now you have granaries to blunt its impact.
Like "hidrobyte" I too am amazed at how little known it is. But one part Sid Meier civilzation and two parts Cataan... this is an absolute GEM of a game and absolutely deserves to join the Good Old Games library.