How is Riverworld described in the novel, The Moon and the Face?

Riverworld is described as an insulated ancient world, where people continue to practice the rituals that link them not only to each other, but also to the river that gives them their food. Riverworld is described as a lush natural setting. When Terje returns there, he notes the beauty of its colors and smells: "The birds were settling back into the trees, little flashes of lemon, chartreuse . . . and there was just the wind, with its invisible weave of messages . . . animal smells, the smell of honey, the smell of rain."