Tikal was the first ancient Maya site that I ever visited, and it remains my favorite one. I've since visited about 20 others, but Tikal still stands above them all.   The combination of the lush jungle and the steep pyramids poking above the canopy with their delicate roof combs above the  top temple rooms was just fantastic.  I loved the combination of the imposing pyramids with the detailed hieroglyphic stellae and the occasional giant stucco mask.  You get it all at Tikal, whereas other places, like Calakmul, for example, disappointed me a little because it didn't have much of the finer art, like stellae, while it had plenty of impressive massive buildings.  When we visited Tikal (1988) you could still climb on any of the structures, although a couple of them required getting up some rickety wooden ladders. I still remember how scary it was to climb the very narrow steps and having respect for the ancient Maya who had to ascend and descend these staircases routinely