Koru is the smallest of the countries on the continent of Ehrian.
Mostly forestland, Koru benefits from rich mineral deposits in the mountains the border it on both sides. The country is roughly split into three sections. Nearest the One Tree at the continent's centre lies a large lake named the Lover's Lake. The communities there rely on the lake for their livelihood and have a deep bond with the land. The middle section of the country is mainly forested and is inhabited by elves and Eladrin who have set up communities on the prime material plane. They constantly fight against the encroaching human settlements and the magical Rail (see below). The One Tree of Koru is in the centre of the forested area, jealously guarded by the drow portion of the populace. As a result, the Church of the One Tree is almost non-existant in Koru in favour of the honour system.
The westernmost portion of the country is swampland, a wild and untamed area that is home to many species of ferocious creature and more than one evil race.
There are very few settlements in Koru that are not walled city-states. Each city is controlled by a Shirei who has ultimate power in his city; the capital, Rida, is ruled over by the Shirei-kan, Haron. The city-states have a brutal honour-based discipline system and the army has a broad scope when it comes to enforcing the law.
The Rail is a magical service instigated by the Shirei-kan and completely controlled by the state. A single-rail rapid-transport system, the Rail allows for fast and relatively safe travel through the forest and swampland. It is also subject to constant guerilla attacks by the elves in the forest.
Both goods and people can be transported by Rail and it is completely state-funded and maintained.