I am flying into Beijing at 05:50 and flying out again at 13:30 that same day. I am wondering if I have enough time to go out into the city and do some sightseeing. I have a visa. I would aim to get back to the airport at around 11:30, leaving me around 4 hours to go into the city. What destinations could I see in that timeframe and still get back to the airport on time. I do not know any Chinese.