The Amber Room was an 11-foot-square hall covered in panels of carved amber and other semiprecious stones.
In 1716, Fredrik William, the king of Prussia (later a part of Germany) presented the Amber Room to Russian Czar Peter the Great. Catherine the Great later commissioned a craftsmen to further embellish the room and moved it from the Winter Palace in St. Petersburg to her summer home in Tsarskoye Selo.
When Hitler's troops invaded the Soviet Union in 1941, his troops took Tsarskoye Selo, dismantled the Amber Room, and shipped it to Königsberg, Germany (Kaliningrad today).
After 1945, the Amber Room was lost. Many suspect that it was destroyed during the war. In 1997, a group of German historian/detectives found someone who was trying to sell a piece of the Amber Room. Police raided the office of a lawyer in Bremen who was trying to sell the work for a client – the son of a German officer who had accompanied the convoy to Königsberg. The son said he had no idea how his father got the mosaic.
The panel, along with a chest from the room which also surfaced, were presented to President Vladimir Putin of Russia.
At the time of this posting, a complete recreation of the Amber Room is nearing completion, and will be opened to the public as a museum. The recreation is being made based almost entirely on WWII era photographs.
Most info taken from a radio report on NPR (National Public Radio), "St. Petersburg's Amber Room, Recreated" May 30, 2003, an interview with Elizabeth Kolbert, billed as "the author of a recent New Yorker article on the Amber Room".