It is actually a giant forest-sized sprawling of groups of Groves, which are the communal groups that Decheeran join and "grow into" as they mature. There is no social value to Sabiak and no government buildings - they have no real government that directs them or their movements (though they do have a "First Speaker" that will pass on the decisions of the whole race if need be) - Sabiak just happens to be a really nice place to live on Atria if you're a tree.
The Great Glade
This is the beating heart of Sabiak, through which - if you wait long enough - every Decheeran will, sooner or later, pass. A broad clearing in the tangled vegetation of Sabiak, its tall, golden grass glistens in the intense light of Orpheon. Decheerans come here to bask in the direct sunlight, without an intervening layer of canopy, as well as to "share sun," or socialize. If Sabiak can be said to have a "governmental center," this is it; when the Decheerans of Sabiak or of all Atria need to discuss matters of great importance, this is often where they do it.
The Cascades exemplify the landscaping prowess of the Decheerans. Three separate streams are merged and plunged over a series of boulders and banks, each carefully engineered to appear perfectly natural. Along the way, they form pools and eddies, secluded coves and showers, before plunging at last into the final pond, the largest body of water in Sabiak. Arboreal life-forms like the Decheerans appreciate a good water feature, and the Cascades are at once water garden and functional district, both decorative and utilitarian: Decheerans can be seen here at most hours of the day soaking their root-tendrils in quiet contemplation or in small groups. Some of the pools are ringed in exotically scented flora; others are heated; still others are filled with fish.
Elanon Glade is one of the oldest and most storied Glades on Atria. Its roots (so to speak) date back to well before the Bushraki Wars, and as such it sprawls across a stretch of excellent forest in northeastern Sabiak, upon the southern exposure of a sun-soaked ridge. The silence beneath the trees seems almost too sacred to break. Decheerans of the Glade, whether long-time residents, still integrating, or just passing through, live in platforms woven into the branches at all levels from the ground to the dizzying heights of the canopy. Elanonians are thought to be somewhat haughty, given the weighty heritage of their Grove, and though they are not accustomed to offworlders, they will gladly speak at length about the history of their people if provoked.
Offworlders Glade is a bit of an oddity. While there is no quarter of Sabiak specifically dedicated to offworlders, aliens tend to find themselves congregating together in this region, surrounding themselves with environs designed to ease the culture shock. Though the great trees are certainly present, the buildings and residences here are built firmly at ground level in most cases. Here can be found embassies from other species, as well as the local administration of the Song Dominion. Native-born Decheerans fascinated with spacers (both Decheeran and alien) also flock to Offworlders Glade, eager to expose themselves to new experiences... and perhaps win themselves a berth bound for strange suns.
The Snapping Fig
The Snapping Fig caters primarily to spacers, as well as native Decheerans who want to share a drink with them. A fixture in Offworlders Glade, it offers fare that would be recognizable to Humans and Nusriza alike, as well as vegetable fare and artificial UV lights for Decheeran patrons. Its smoky corners are often the scene of intense negotiations between captains and locals seeking to purchase exotica or a place on a crew.
Sabiak Below refers to the complex network of passages, transit lines, and utility spaces beneath Sabiak. Here is where the technological heritage of the Decheerans is truly evident; above, the UV lamps are woven into the tree branches to give the appearance of softly glowing flowers, while here they are exposed and evident, though the occasional planter still lends the race's favored biological hue to the environment. Transit cars will carry travelers anywhere else on the planet - including out to the fringe of the Greenwilds. Also here are several of the laboratories where the Decheerans use enormous machines to generate the pressures necessary to refine diamene, putting their famed focus and calmness of mind to work producing the processors the entire galaxy depends upon.
The Greenwilds stretch out beyond Sabiak, in the mountainous, heavily forested interior. Unlike the lowlands, with their rich soil and relatively dense populations, the Greenwilds are populated mostly by loners, hermits, and wildlife. Where Sabiak is tame, the trees arching overhead like a vaulted cathedral roof, the Greenwilds are, well, wild. In many areas, the vegetation is so tangled as to form a barrier, and in the lower reaches, the roots form complex and darkened caverns filled with the scuttling of insects and the slow pulsing of the heartbeat of the trees. This region is kept wild partially out of defense to natural balance, and partially as a nod to the race's history, when the Greenwilds were a destination for hermits, rebels, and prophets whose words would later go on to change the course of Decheeran history.
The Pinnacles soar up above the canopy, rocky and barren. These spires of rock have been the destination and the fastness of Decheeran hermits since the earliest days of their race, and the rocks are carved with spiraling glyphs dating back centuries, even millennia. Atop some of them can be found Decheerans seeking solitude for whatever reason, even today.
The Tangle stretches from the canopy to the roots, and is the chaotic, confusing tangle (thus the name) of trees and vines that comprises the middle layers of the forest. It resounds with the sound of the tree lizards and birds that hunt throughout its verdant spaces. Its base is a tightly-woven mass of vines, decaying plant material, and root mats called the horizon, which serves as the closest the Tangle has to a "ground." It is not uncommon for young Ry'nari to come here to hunt the strange quarry as part of an adolescent proving.
The Rootsnarl is the network of caverns formed by the enormous roots of the great trees above, and despite appearances is almost entirely above ground. Despite this, it is pitch-black here, filled with the dripping of rainwater that filters its way through the horizon and collects in great basins formed by the roots. Here, strange pale insects and luminous eels swim, glimmering in the darkness. It is said by some Decheerans that deep thrumming of water being drawn upward through the billions of roots is the song of the Tal, though it's not clear what they mean since the Tal isn't generally viewed as a personified force.