At the northeast tip of GAM, the statues of "Los Indios Verdes" (The Green Indians) mark the end of the city, and the beginning of the road towards Teotihuacan.
The "Green Indians" represent Aztec kings Itzcóatl and Ahuizotl.
But you have to really want to see the statues, the place is awful and the traffic, infernal.
These statues, were originally at Paseo de la Reforma, but people didn't like them, so they were expelled to the extreme outskirts. Now the city has catched up, and there is also a movement that wants them back in their original place. (I have mixed feelings about it, poor "Green Indians" have been neglected so much, but the statues are not good).