Completed in 1791, this beautifully proportioned Georgian building has a long classical facade of graceful pavilions, arcades, and a central dome topped by a statue of Commerce. The 14 keystones over the doors and windows are known as the Riverine Heads, because they represent the Atlantic Ocean and the 13 principal rivers of Ireland. Although it burned to a shell in 1921, the building has been masterfully restored. The exterior is the main attraction here, and most of the interior is closed to the public; those with a real interest in finding out more about the building can drop by the visitor center, which has exhibits telling the story of the building, burning, and reconstruction.