Long Street is an amazing place at night. It's lined with restaurants and bars and has loads of people streaming up and down all night long.
Long is a one-way, with it's parallel neighbour, Loop, running in the opposite direction. This particular section is near the top of the road - where it's pretty safe to walk around at night. The middle, or bottom is a lot quieter and not necessarily quite as safe, and I guess is a place that I'd only really walk around during the day.