Location from Memory, Sorrow, and Thorn by Tad Williams
Boat on the Ocean of Trees — the last living Sithi city, woven into the deep forest like a dream that refuses to end, beautiful and fading and nearly impossible for mortals to find.
Jao e-Tinukai'i is what the Sithi became after they stopped building in stone. After the Fall of Asu'a, they retreated into the Aldheorte and created something new — a city of fabric and living wood that shifts with the seasons. It's gorgeous and heartbreaking, because it's also the last one. The only thriving Sithi settlement in a world that once held nine great cities. Mortals who find it — and almost none do — describe it as a dream. The light is different. The air smells of blossoms that don't exist in the mortal world. Time moves strangely. The Sithi who live here are ancient, graceful, and dying — not individually but as a people, slowly declining, their population falling, their cities emptying one by one. Simon's arrival here is one of the trilogy's most luminous sequences — a mortal boy standing in the last city of the immortals, seeing beauty and extinction in the same glance.
Not built so much as grown — elaborate fabric structures seamlessly integrated into ancient trees, connected by graceful bridges of shimmering white stone that seem haphazard until you realize they follow patterns too complex for mortal geometry. The Summer Gate is formed by twin towering hemlocks with trunks vast enough to be columns holding heaven. The Yasira — the great gathering tent — has a center pole fifty ells high made from a gigantic ash tree, and butterflies gather inside it for important decisions.
Also known as: Jao e-Tinukai'i, Boat on the Ocean of Trees