This area is a limestone sculpture called Rim Stone which is formed from the group of many thousands of year. It is formed from the flow of water, which has high sediment content. As the water passes over the forming rim, more and more sediment is deposited.
Eventually, the water cannot flow freely and begins to collect behind the rim, cascading down to form another rim below.
This process ends up with the enchanting gradual staircase of pools. Now, there isn’t any water passing in this area, so we are left with Picturesque Rim Dam.