The Twilight Archipelago is volcanic island arc comprised of a total of 168 islands, with the largest, Ellislanr, forming the primary population center. The Archipelago covers a total of 502,152 km2 land area, including 152 km2 of the land used by T'lassas Arcology, but not including the area covered by T'bomiex Arcology - an independant Arcology Statistical Area.
Approximately 90% of the collective landmass of the Archipelago is protected woodlands, designated as such during the Era of Reunification in an attempt to forestall deforestation. The world's oldest living tree, the Jodin Lege, is estimated to be 35,000 years old.
The remaining approximate 10% of the collective landmass is mountainous, and represents the total uninhabitable area of the Archipelago.
The climate of the Twilight Archipelago is perhaps the most unique regional feature. Despite being a sub-tropical island chain, the climate is kept at a moderate 18 degrees C during the summer and 15 degrees C during the longer winter.
The Twilight Archipelago and its protected forests provide a natural habitat for over 1,500 unique species of flora and fawna. Ranging from temperate coniferous forests on the outlying southern islands to subtropical massleaf forests on the main island of Ellislanr, the breadth of life represented here that is not found anywhere else on Tinris makes the Archipelago unique.