Beijing is surprisingly unpleasant to walk.
Every metro has 4 exits, and you’ll be damned if you take the wrong one. You can’t just walk back into the metro, for that will cost you a fee. And streets are very nearly uncrossable, almost everywhere. You best cross only on traffic lights. The light that the traffic light shows is of no importance; but near traffic lights, the traffic is slow enough to attempt a crossing.
Here’s an example. We live around 70 meters away from the platforms of the Beijing north railway station. But as you might be able to make out in the picture, the station has no exit in our direction. It has only one exit, in the top left of the picture.
To get from the station to our hotel (where the picture was taken), you walk along the top edge of the picture to the right, for over a kilometer, walk around a subway stop, and then walk to our place, for a total of 2 kilometers.