I have first played this game at my grandfather's home, back in the late 90s, and I think it was already in 1998, so a short time after the game came out (1997). I love the game so much, because it gave me my undying love for ancient history, together with Civilization II. Despite the fact that it is a game in its core, the developers made sure that there is plenty of information on the cultures you are playing, at least for the ones of the campaign. So, it is great for the casual strategic player, but also great for fans of ancient history. Leading your nation from the Stone Age to the Iron Age and watching it develop is just so good and due to its realistic setting and units, despite the funny language invented by the developers, it is so much better to me than all of those fantasy and Science Fiction videogames, including Command & Conquer, believe it or not. And the song "Cave" is truly the definitive Age of Empires song for me, together with the intro song. And the intro movie and also the other movies are still wonderful to be watched today, almost 30 years later. Actually, I do not remember a single time during which I did not watch the intro movie at the start of the game, that's how beautiful the intro is.
Also, the game's AI is quite aggressive and although the game looks simple, it is very tactical and one must get used to it at first. Many people complain about the fact that the unit limit is set at 50, yet I have read in an interview from that time within an old German videogaming magazine (PC Player) that the developers wanted it this way, to make sure that you play this game tactical, instead by just flooding your opponent with giant armies. And yes, that perfectly makes sense to me. Again, it is a strategy game, so you use your brain instead of a boring rush.
I just love the first Age of Empires, even more than the second one, and I will never forget all the great times I've had with it. I hope, with the help of GOG, I can soon relive my 90s youth!