wildlife in the city

The other night I was walking to Jia's for a late dinner after work. I caught a glimpse of a rock out of the corner of my eye... but it wasn't a rock, it was a really big snail in a shell. The snail was wandering about the tile steps with nowhere to go. I figured it probably escaped from someone's dinner.
On the way home, I saw it again--this time Jia was with me. She ran home to get her camera. This thing was huge We fed it a few plant leaves and later moved it to the grass in the hopes that no one would kill it for fun.