A boundless wilderness, Olympus is the land thought of by most when they hear the name Arborea. The most well-settled portion of Arborea, Olympus (also known as Arvandor) is home to both the Seldarine and the Olympians, two of the multiverse's more prominent pantheons. Olympus is also home to the Gilded Hall, the massive festhall of the Sensates, located here to take the best example of the ammplified passions and sensations the plane has to offer. However, Olympus is certainly not entirely settled - just as the rest of the plane, Olympus is the realm of the Quest. Specifically, the landborne quest, the epic journeys over hill and dale to accomplish great deeds for no reason but to say they have been done. As such, Olympus can be amongst the most dangerous of the Upper Planes, for what good would a quest be if it were easy?
In the settled regions, the fields of Olympus are covered not by open grassy meadows but by vast arbors of grapes or olives, waving fields of wild grain and corn, and pastures filled with hundreds of cattle, sheep, and goats. The woods consist of untended orchards of fruit- and nut-trees of all types, dense thickets of pine, cedar, mahogany, and maple. And many rivers and streams, including the River Oceanus, wind through the settled regions, filled with fish and other sea life of all types. Saturated with the spirits of nature, the lands of Olympus are deeply bountiful, and the people of Olympus do their best to use this fact without exploiting it, taking nature's gifts without offending the fae that grant it. While the unpredictable weather can at times wreak havoc on the people of Olympus, for those that properly honor the spirits of nature, the fields and crops always seem to be spared the worst.
However, if one moves beyond the towns and villages, one finds a much different tale in Olympus. Its landscape there is made up of massive, craggy mountain ranges cut between by vast fields, rolling hillocks, thick forests, and rushing rapids, with all manner of ancient and mythical beasts walking the land. There, the weather of Arborea grants little succor to those in the wilds; while those that properly honor nature have somewhat less to fear, a freak thunderstorm or shower of hail is always something of which to be wary. As one heads further out to the unsettled regions, one will even encounter the occasional coastline, almost always marked by steep cliffs or rugged fjords rather than the gentle sandy beaches of other seas. It is only at these coasts that Ossa can be reached without a portal or path, sailing straight away from the lands of Olympus and into the stormy seas, where eventually one layer gives way to the other.
Of course, the most blatant landmarks in Olympus are the homes of the two above-mentioned pantheons, so prominent that the entire layer is known by their names: Olympus, home of the Olympians and their eponymous mountain, and Arvandor, home of the Seldarine. Due to the odd properties of the plane, both realms hold the position of highest point in the layer, and neither is visible from the other, the two realms separated by hundreds of miles of untamed wilderness. Though each wild in their own way, these two realms hold the largest settlements in the layer as well, and nearly all travelers to Olympus will end up stopping at one or the other.
These were not always so, however. Long ago, eons in the past, Olympus was not home to the elves and Olympians, but rather the giants and titans, both occupying the realms now held by the former. Each took this layer as home, until confronted by the more recent pantheons. The elves were the first invaders to Olympus, Corellon leading the Seldarine in an invasion upon the land now known as Arvandor. It was a long, hard war, but the Seldarine triumphed, banishing all the giants but Iallanis, and allowing her to remain only grudgingly; even today, giantish ruins can be found deep in the darkest forests of Arvandor. Soon after the giants were exiled, the Olympians arrived to wage war with the titans, their forefathers, in a much shorter but far bloodier war. When that conflict was concluded, all the titans involved in the war were exiled to the prison plane of Carceri, with only those that had abstained from the conflict — Rhea, Prometheus, and others — allowed to keep their homes. Both pantheons of Olympus were indeed founded on wars of occupation that resound even today, and even now there continues to exist a grudging allegiance between the giants and the titans.
- Manual of the Planes, pp.145-146
- Planes of Chaos - Book of Chaos, pgs.39,41-50