My three most memorable moments were:
1) First leaving the Great Plateau on the way to see Impa in Kakariko village. Crossing that first bridge and seeing the first shrine imagining what was out there in the world.
2) Being on mountains and high areas seeing across the whole world. Then seeing just how far the towers and what you can see was.
3) going into the lower area's. I spent most of my time early up high to see what was around. I was missing so much below. Just like that trench leading to the Forbidden Kingdom.
The only thing that have made the game better would be a few more towns and traditional dungeons.