I don't know how familar you are with Peking Duck, sorry to go through this just in case other people don't know.
The most famous place for Peking Duck is called Quanjude since 1864, obviously it did not start from Grand Hyatt
Check this official website
http://www.quanjude.com.cn/e_about.html
If you think Peking Duck in Grand Hyatt is great, try the original one. Do remember though, do NOT take the set menu or go upstair eating in a small room. They are not as good as the normal ones served in the big hall, and cost too much for nothing.
If anyone has few hours in Beijing, go to Ya Yun Cun Quanjude Roasted Duck Restaurant at No 309, Huizhong Beli, Chaoyang District (email
[email protected], tel: +86 10-64801685/86), it is near the North 5th Ring Road. From the airport, there aren't much traffic at that direction.
The other option is Guomen Quanjude Roasted Duck Restaurant at the Ground Floor of Jing Xin Building, No 2. East 3rd Ring Road North, Chaoyang District (email
[email protected], tel: +86-10-84492759/60). Although this branch is closer to the city centre, but it's next to the airport express highway, so you shouldn't have any problem with traffic. Oh, if you know where Hilton hotel is, this restaurant is next to the Hilton.
The best branch, and the 1864 original Quanjude branch is in Qianmen, but that's too far to reach from the airport, if you only have few hours.
I don't think they take reservations, becasue nobody can estimate the traffic in Beijing, even locals. So queuing is the only way for it. I normally go to Qianmen branch (I love the duck so much, that's why I know all of this), and queue for 30 minutes.
The good thing is I normally eat at 7:30, as most of fellow travellors here are from the western world will do, not as early as local Chinese. So we all avoided the huge queue from 5pm to 6:30pm.
Last thing I want to say is, the issue certificates for each duck they serve (although sometimes they run out of them), and all certificate are numbered since 1864 (so we've been told

). The last one I had was 1.2 billion or something around that number, it's a nice touch and brings memory back.
Enjoy your duck!