The seat of Vietnamese power for nearly thirteen centuries, from the Đại La period through the Lý, Trần, and Lê dynasties. Most of what stood above ground is gone. What remains is the Đoan Môn south gate, the stone-dragon stairs of the Kính Thiên foundation, the Hậu Lâu rear pavilion, and the live archaeological pit at 18 Hoàng Diệu where successive palaces are stacked in cross-section. UNESCO listed the site in 2010, the year Hà Nội turned a thousand.