Final Fantasy VII/The fall of Sector 7

(Todo: May need some expansion)

After the cutscene you splash down in the sewers. Talk to Tifa and Aerith to wake them up, but before you wake up the other of them, be sure to check up your healing and materia if necessary. Of course, Don Corneo wouldn't have thrown you into the sewers expecting the foul stench alone would have killed you!

There's a single notable item in the sewers, a Steal materia. Getting back to the surface after beating the boss should present no problems, the enemies are relatively weak.

Train graveyard
The train graveyard is easier than it looks. The onlu thing that probably confuses at first is that the train cars may have holes on their roof so figuring out where the items are is more difficult. Use the ladders and ramps and whatnot to cross to the other side. There's a Hi-Potion and Ethers [I think] here.

On the other end of the train graveyard, the trains block your path. Hop on the nearest engine that has a door open. The engine will push one of the cars off the way. Then hop on the another engine, and the way clears.

Boo-ya!