A pedestrian only mall with hundreds of shops. This is the heart of Adelaide ahopping I am told. There are a few large department stores (Myer, Woolworths, David Jones, Target) and many small boutiques and shops. The wares include clothes, records, jewelry, books, candy, souvenirs, etc.Notably there is RM Williams, which is known as an authentic outback outfitter; Haigh's chocolates - a pricey but delicious chocolatier and the oldest in Adelaide; the Opal Underground Mine, where you can learn about the opals mined in South Australia, which are much different than the pearly white ones we have in the states (it'll cost you to bring a nice one home however).
There are also brochure stands at either end for tourists, and I recommend stopping there first to help you plan your time in Adelaide. At the Renaissance Tower you can ride the glass elevators up and get a nice bird's eye view of Adelaide. It's worth some of your time if you like shopping.