The most convenient way to take a taxi, but it's not fast. Because the time to go out is the morning rush hour, it is easy to get stuck in traffic on the ground. The National Library is on Metro Line 4, take Dongzhimen, and transfer to the Airport Express (without getting off the subway), which is the fastest way.

It takes 30-40 minutes from Dongzhimen to Terminal 3 by airport express.

It takes about half an hour from the National Library to Dongzhimen.

The plane needs to board half an hour in advance.

Going through security check in the morning is also the peak period. How long it takes depends on whether you take an international flight or a domestic flight. The international flight is about 1.5 hours (take a small train to T3E), and the domestic flight is 1 hour.

This adds up to the time you need to move forward.