Grape Valley is a planted corridor in the Turpan basin, long enough that a vine trellis can fill the view. The city's own report of a 2023 visit describes water beside the vines and rooms where bunches hang in rows. The contrast is the story: outside, heat and bare slopes; inside the valley, irrigation and leaves. The visitors' comments on flavour stay in that livestream.
From the journal
Grapes, then a room of shade
In Grape Valley the fresh fruit and the drying room are part of one walk, from irrigated vine to hanging bunch.
In the same city · Turpan ↗A green cut in a hot basin
What the room is doing
The drying room is a building with openings, so air moves through hanging fruit. A bunch cut from the vine loses water there and becomes a raisin. Colour and sweetness vary by variety and by how long the fruit hangs. Those differences are real, and they are not settled by one person's comment on a livestream. The useful fact is the sequence: irrigate, pick, hang, wait.
The fruit depends on the channel
The karez park page puts drying rooms next to vines watered from the underground system. Fruit and hydraulic engineering belong in the same basin for that reason. A raisin is an ordinary object. The room that makes it is a local answer to air that would otherwise take the water from a ditch before the vine could use it. Qocho and Yar, nearby, needed the same kind of water for a city rather than for a trellis.