The Waterfall is on the north of the island. From the waterfall you can walk west to the Sacred Mountain, south to the Meadows Park and northeast to Red Heat.
At the moment there's only one place you can visit at the Waterfall: the Tuxedo & Evening Dress Shop.
Tuxedo & Evening Dress Shop
As a premium user you can buy different evening wear here. They are some of the most expensive clothes you can buy in this game.