The Hall of Benevolent Longevity is a ginormous throne room hall much like the Hall of Supreme Harmony at the Forbidden City.
The phoenixes next to the dragons represent the Empress:
This plaza was our last stop inside the Summer Palace, and it is just inside the main gateway; we came in through the back door and have been working our way through the private parts of the Palace - the gardens and the residential courtyards - and have at last arrived at the public space. In the Forbidden City the proportion of private to public space favored the latter; here it is reversed.
In the front part of the courtyard stands a statue of a cool Chinese mythical beast, the Qilin:
Qilin have the head of a dragon, the antlers of a deer, the skin and scales of a fish, the hooves of an ox and tail of a lion, and they can detect lies and punish wrongdoers. This one is here because this is the place that Cixi heard official reports and conducted state business; he was supposed to intimidate the officials into telling the truth.
The officials would come all the way out here to give their reports, come in the front gate, present their reports, kowtow to the Empress beside the kirin statue, and then turn around and leave, leaving the rest of the complex as the private preserve of the Imperial family.