Monticello’s Cabinet, Jefferson’s Study

Monticello is the primary plantation of Thomas Jefferson, the third President of the United States, who, after inheriting quite a large amount of land from his father, started building Monticello when he was twenty-six years old.

Part of a "suite" of Jefferson's private rooms, along with the Book Room, Greenhouse, and Bedroom; adjoins Jefferson's Bedroom via a passage and an alcove bed open on both sides; plan based on an octagon, a favored architectural shape for Jefferson.

http://www.monticello.org/site/house-and-gardens/cabinet