Final Fantasy VII/The Forgotten Capital

Aerith has gone to the Forgotten Capital. She has left you her accessory (if any) and all Materia.

Sleeping Forest
There isn't a great deal of stuff to do in the sleeping forest. On the first screen, the Kjata materia is floating through the branches. Grab it.

On the second screen, there's a box containing Water Ring. This is also a great place to train if you want tons of AP.

After the next screen, you make a brief jaunt to the world map, after which you find yourself in...