Qumran was a real compound at the north end of the Dead Sea where the religious sect known as the Essenes lived and worked. In our stories, Nathan is part of this community, and Jotham, Bartholomew and Tabitha all end up there at some point.
As in the stories, there really was a scriptorium at Qumran -- a room where the Essenes made copies of the scriptures. They hid these copies in urns in about 45 caves outside the compound. These are the scrolls Jotham finds while hiding there with Nathan.
In 1947 a native of the area discovered the caves, and the urns containing the writings. These are what's known today as the Dead Sea Scrolls.
Below are some artists' conceptions of what Qumran looked like, as well as photos of the cave and the site as it looks today.

An overview of the compound as it probably looked in Jesus' time.


Looking toward the NE and the caves.

A gate and guard tower.

The scriptorium.

Much of the industry of Qumran dealt with making urns in which to store scrolls.
Thanks to the UCLA Virtual Qumran Project for the above images. You can see many more at their website, VirtualQumran.com.

A photo of the Qumran caves as they appear today, and as visited by the author in 1980.

The ruins of Qumran outlining many of the walls. Note the Dead Sea in the distance.
Our thanks to eBibleTeacher.com for these images. You'll find many such images and other church materials at their website.