Just to prove the mist wasn't pollution, here is the same view later on in the day:
Fúlóng Píng (伏龙坪) is a poor Hui area, perched on the clay hills to the south of Xiguan Shizi.
UPDATE (27 AUG)
Back to my original route...
This was my first chance to get a good view up into the area:
I followed the alley along, until I came to an opening, which looked down towards Jiěfàng Mén:
Finally, I worked my way to the centre of Fúlóng Píng. Traffic can drive up via a road from Āndìng Mén (安定门), at the south end of Zhōngshān Lù (中山路). It felt like a small country village up there.
Now on the 'main' road, I was able to continue upwards, heading sometimes south and sometimes east, along the hillside that eventually arrives at Lanshan.
Towels and a mop, drying outside a small hairdresser's:
Here was the view from Fúlóng Píng, looking west over towards Huálín Píng (华林坪), another Hui area, which can be reached by heading southwest from Jiěfàng Mén:
By this stage I was back on familiar territory, having used this road to cycle up Lanshan several times in the past. I stopped off at a small mosque, and then a few hairpins later, reached a lookout terrace.
From here, a tree-shaded path continued up, and would lead you along the ridge overlooking Wuquan Shan, and eventually to Lanshan.