Teledahn is one of the five journey ages in Myst Online: Uru Live. The age is distinguished by its large building sized mushrooms that grow out of the marsh bellow.
Taken from the a 2004 archive of the DRC site: In the year 8990, Grand Master Mararon of the Guild of Writers wrote Teledahn for his good friend and fellow member of the High Council Lord Hinahsh. Lord Hinahsh was also Grand Master of the Guild of Caterers. The age was given to the Lord as a 250th birthday present and was a beautiful age covered with giant mushrooms that grew out of a warm water that covered most of the surface of the Age. Though Hinahsh spent a relatively small amount of time on the Age, he found enough time to study and experiment with the mushrooms and the numerous spores that they produced. Being that he was a gifted cook, Hinahsh began to develop a unique bread recipe from the spores that went out to become a delicacy amongst the elite of D'ni
After his death in 9005, the Age was given to the Guild of Caterers. While the Guild ran a sucessful operation there for a number of years, eventually the machinery and industrlialization was too much for the environment. The Age was thrown away, cosidered "used up".
Rumor has it that it was found again by a man named Manesmo while rummaging through a trash heap.
Records indicate an investigation was started in 9396 concerning the storage and trading of slaves, with the harvesting of spores as a front for the operation. The Guild of Maintainers kept the investigation quiet so as to not give Manesmo time to cover his operation but he always seemed to be one step ahead of them. It would seem the truth was never uncovered before the Fall of D'ni. [needs editing] 
One you have linked to Teledahn...