Mobile Suit Gundam
43 episodes https://www.youtube.com/watch?v=OIcQrL3tYnA
Mobile Suit Gundam, often referred to as 0079, is an absolute classic. It is seriously one of the most impressive mecha shows I have ever seen. The action, pacing, and intensity are masterful, and I'm sure that this first show played a big role in propelling the Gundam franchise into the mainstream. The show only fails at one point - the animation and budget, which was quite poor at some points. It should be noticeable if you pause the show while Gundam is moving, but otherwise fine.
I love this show, 10/10.