Arborlon is the only large Elven community described in detail, but there is another one in the Westland known as Wing Hove. These Elves consider themselves a separate people from the Elves of Arborlon, although their ancestors originated from Arborlon.
Arborlon is situated atop a high forested bluff known as the Carolan, which rises steeply from the eastern shore of the Rill Song. This positions the city both high above the surrounding land and deep within a densely forested area. The city proper, where the palace is located, is on the east side of the Carolan, with the Gardens of Life and other isolated cottages to the west; however, the entire area is known as Arborlon.
The Carolan provides a measure of security to Arborlon, serving as the city's boundaries on the east, north, and south, with the Rill Song to the west. The entrances to Arborlon are to the west and the east, with impassable mountains to the north and south. On the west side of the Carolan, there is the Elfitch, a series of seven stone ramps and iron gates which lead from the top of the Carolan to the base of the bluff at the east bank of the Rill Song. On the east side there are smaller stairways which lead down into the Valley of Rhenn.
Age of Man
During the Age of Man (and presumably even earlier in the Age of Faerie), Arborlon was originally situated deep in the forests of the Cintra, south of Redonnelin Deep. In the Age of Man, humans knew the Cintra as the Willamette National Forest in Oregon. The descriptions of Arborlon at this time match descriptions from the time of the War of the Forbidding, indicating that the city itself remained largely unchanged throughout the millenia.
The massive destruction caused by the Great Wars (and the demons who brought the Wars about) posed an existential threat to the Cintra Elves. The Ellcrys instructed her Chosen Kirisin Belloruus to find and use the Loden to encapsulate the Ellcrys, Arborlon, and the Elves and transport the entire Elven nation to a safe haven.
Kirisin succeeded in finding the Loden and removing the Elves from the Cintra. He joined the caravan of Hawk, a gypsy morph, who ultimately led those who wished to survive the Great Wars to a safe, sheltered valley located in the mountains several weeks journey on foot east of Spokane. Once there, Kirisin used the Loden and released Arborlon onto a forested bluff (which would later be known as the Carolan), freeing the Elves once more.
Hawk used the last of his power to encircle and protect the valley and the people he had led into it in a magical wall of mists. After the final nuclear missiles were launched and the landscape of the Earth went through tremendous upheavals, changing into what would become the Four Lands, Arborlon and the rest of the valley's communities remained intact and protected.
Arborlon would thereafter remain in the place where Kirisin put it, even after the mists finally dissipated centuries later and the valley was once again connected to the outside world.
War of the Forbidding
Arguably the biggest threat faced by Arborlon was during the reign of King Eventine Elessedil, when the Ellcrys began to fail and Demons began breaking through the Forbidding. Demons managed to conquer the Elfitch and had even begun entering the Gardens of Life. They were only saved when the Chosen Amberle Elessedil, the King's granddaughter, transformed into a new Ellcrys.
Arborlon was moved to Morrowindl, a tropical island about 200 miles across off the coast of the Westland in the Blue Divide, about 100 years before the reign of Wren Elessedil. The Loden was used to remove the entire city of Arborlon, including the Gardens of Life and other trees and vegetation, from the Carolan. On Morrowindl, Arborlon sat atop a bluff similar to the Carolan.
When Morrowindl began to become dangerous due to the spawning of many dangerous creatures around the island, the Keel was constructed around Arborlon. It was a large stone wall, constructed by hand, but maintained by the magic of the Loden and the Ruhk Staff, a staff used to channel the Loden's power. The Keel had three sets of gates leading out of the city, one main gate and two smaller ones. There was a dry moat just inside the city walls, and there were also dozens of places where the moat was bridged to provide access to the top of the Keel.
Using the Loden, Wren Elessedil successfully transported Arborlon out of Morrowindl and placed it back in its prior location in the Westland, atop the Carolan. Since the time of Wren Elessedil, Arborlon's location has not changed.