Slotsholmen is the seat of national government and a veritable repository of historical sites. Located on a small island and separated from the city centre by a moat-like canal, Slotsholmen's centrepiece is Christiansborg Slot, a large palace that is home to Folketinget (the Danish parliament) and various government offices.
Several short bridges link Slotsholmen to the rest of Copenhagen. If you walk into Slotsholmen from Ny Vestergade, you'll cross the western part of the canal and enter the large main courtyard of Christiansborg Slot, a large palace that is home to Folketinget (the Danish parliament) and various government offices. The main courtyard, which was once used as royal riding grounds, maintains a distinctively equestrian feel, overseen by a statue of Christian IX (1863-1906) on horseback and flanked to the north by stables and to the south by carriage buildings.
The stables and buildings surrounding the main courtyard date back to the 1730s when the original Christiansborg palace was built by Christian VI to replace the more modest Copenhagen Castle that previously stood there. The grander west wing of Christian VI's palace went up in flames in 1794, was rebuilt in the early 19th century and was once again destroyed by fire in 1884. In 1907 the cornerstone for the third (and current) Christiansborg palace was laid by Frederik VIII and, upon completion, the national parliament and the Supreme Court moved into new chambers there.
In addition to the sights listed here, visitors can enter Christiansborg Slotskirke, the castle's domed church, which was set ablaze by stray fireworks in 1996 and has since been painstakingly restored.