To take a train from Beijing international airport to the imperial palace museum

Oh, you must refer to the Forbidden City. To reach there by train, you can take Airport Express Train to Dongzhimen first. Transfer to subway line 2 to Jianguomen, where transfer to line 1 and get off at Tiananmen East. Leave exit A or B and you can walk north for around 0.8mi to the attraction. The whole trip takes around half an hour.

By bus, you can take shuttle bus line 1 to Guomao and then walk to Guomao subway station to take line 1 to Tiananmen East. This way takes around 45min.