The easiest and probably coolest way to get an impression of Tian'amen square. The bike route on the north side is usually open in both directions - no identitty checks on the way ;-) Very wide bike lane in west-east direction. You should not stop (the police does not like this), but cycling (very) slowly is fine. Many cyclists are taking photos, so be a bit careful in thw crowd. Really one of the best experiences in Beijing.