Bishu Shanzhuang, also known as the Imperial Summer Villa and the Mountain Resort, is the centerpiece of Chengde's historical imperial resort area. It's also the biggest Imperial Garden in China, earning it a listing as a UNESCO World Heritage Site in 1994. The complex's walls enclose 5.6 square kilometers (2.1 square miles) of gardens, lakes and buildings that housed a succession of Qing emperors, serving as a secondary palace where affairs of state were conducted when Beijing's Forbidden City grew too uncomfortably hot in the summer ("Bishu Shanzhuang" translates roughly to "Flee the Heat Mountain Resort").

The Manchu Qing emperors (1644-1911 AD), as something of outsiders to predominantly Han China, were greatly concerned with the question of how to rule a vast, multi-ethnic nation, and Chengde embodies the nature of their approach: The grounds of Bishu Shanzhuang symbolically bring the diversity of China together in a tidy, unified package—buildings and gardens allude to famous landscapes and structures around China, as well as the dominions of the Tibetans, Mongolians and other members of contemporary China's ethnic minorities.

Built between 1703 and 1792, the Kangxi, Qianlong and Jiaqing Emperors presided over the Mountain Resort's development, with the son and grandson adding to the accomplishments of the patriarch Kangxi. The first thing you'll see upon passing through the main gate (Lizhengmen) is the palace quarter, which is, at first glance, surprisingly modest in appearance, consisting of four groups of low wooden buildings whose understated Manchurian-style architecture reflects the northern origins of the Qing emperors. The relatively humble exteriors, however, belie the rich and ornate interiors. Everything is exquisite—writing brushes, calligraphy, scrolls, ceramics, weapons and antique furniture fill the restored rooms of spaces where emperors and their families, consorts and advisors worked and played.

The site was originally chosen on an imperial hunting expedition, and the park extending north from the palace makes it clear how highly the Qing prized China's rich and bountiful countryside. Paths lead through pleasant woodlands, grasslands and rockeries, past areas landscaped to resemble famous scenes from southern China's mountains and rivers, the broad Mongolian plains and other parts of the empire. You could spend hours rambling through the grounds, exploring pagodas, Mongolian yurts, the serene compound on the Island of Midnight and Murmuring Streams, the impressive Wenjinge (Knowledge Imparting Library) and numerous other delightful spots.

In addition to the three aforementioned emperors, subsequent rulers also sought relief from Beijing's heat here, all the way through to the Xianfeng emperor, who died on the premises in 1860 after having suffered the indignity of being forced to cede territorial rights to encroaching European powers. Xianfeng's death at the Mountain Resort, along with that of his predecessor Jiaqing, lent it a reputation for bad fortune among subsequent generations, and from 1860 on the grounds were increasingly neglected, falling into disrepair until restoration work commenced in the 1980s.